合肥市50中新2018-2019学年九年级(上)开学考

2018-2019学年安徽省合肥五十中东校区九年级（上）第一次月考数学试卷一、选择题（每小题4分，共40分）1．若＝，则下列各式中不正确的是（）A．＝B．＝4C．＝D．＝2．已知y与x成反比例，并且当x＝3时，y＝4，当x＝4时，y的值为（）A．1B．3C．7D．123．已知线段a＝10，线段b是线段a上黄金分割的较长部分，则线段b的长是（）A．5（+1）B．5（﹣1）C．10（﹣1）D．5（+3）4．在比例尺1：10000的地图上，相距2cm的两地的实际距离是（）A．200cm B．200dm C．200m D．200km5．如图，抛物线的函数表达式是（）A．y＝﹣x2+x+2B．y＝﹣x2﹣x+2C．y＝x2+x+2D．y＝x2﹣x+2 6．如果矩形的面积为6cm2，那么它的长ycm与宽xcm之间的函数关系用图象表示大致是（）A．B．C．D．7．已知点A（﹣3，y1），B（﹣2，y2），C（3，y3）都在反比例函数y＝的图象上，则（）A．y1＜y2＜y3B．y3＜y2＜y1C．y3＜y1＜y2D．y2＜y1＜y3 8．关于抛物线y＝x2﹣2x+1，下列说法错误的是（）A．开口向上B．顶点坐标为（1，0）C．对称轴为直线x＝1D．当x＞1时，y随x的增大而减小9．已知二次函数y＝ax2+bx+c的图象如下，则一次函数y＝ax﹣2b与反比例函数y＝在同一平面直角坐标系中的图象大致是（）A．B．C．D．10．如图，抛物线y＝ax2+bx+c（a≠0）的对称轴为直线x＝﹣2，与x轴的一个交点在（﹣3，0）和（﹣4，0）之间，其部分图象如图所示．则下列结论：①4a﹣b＝0；②c＜0；③﹣3a+c＞0；④4a﹣2b＞at2+bt（t为实数）；⑤点（﹣，y1），（﹣，y2），（﹣，y3）是该抛物线上的点，则y1＜y2＜y3，正确的个数有（）A．4个B．3个C．2个D．1个二、填空题（每小题5分，共20分）11．如图，P是反比例函数图象在第二象限上的一点，且矩形PEOF的面积为6，则反比例函数的表达式是．12．如图，一抛物线型拱桥，当拱顶到水面的距离为2米时，水面宽度为4米；那么当水位下降1米后，水面的宽度为米．13．如图，已知DE∥BC，EF∥AB，现得到下列结论：①；②；③；④；其中正确比例式有（填序号）．14．已知二次函数y＝x2﹣2mx（m为常数），当﹣1≤x≤2时，函数值y的最小值为﹣2，则m的值是．三、解答题15．（8分）如图，l1∥l2∥l3，AB＝AC，DF＝9，求EF的长．16．（8分）如果二次函数的二次项系数为l，则此二次函数可表示为y＝x2+px+q，我们称[p，q]为此函数的特征数，如函数y＝x2+2x+3的特征数是[2，3]．（1）若一个函数的特征数为[﹣2，1]，求此函数图象的顶点坐标．（2）探究下列问题：①若一个函数的特征数为[4，﹣1]，将此函数的图象先向右平移1个单位，再向上平移1个单位，求得到的图象对应的函数的特征数．②若一个函数的特征数为[2，3]，问此函数的图象经过怎样的平移，才能使得到的图象对应的函数的特征数为[3，4]？四、（每小题8分，满分16分）17．（8分）关于x的函数y＝（m2﹣1）x2﹣（2m+2）x+2的图象与x轴只有一个公共点，求m的值．18．（8分）已知线段a，b，c满足，且a+2b+c＝13．（1）求a，b，c的值；（2）请再求出一个线段，使这个线段与线段a，c这三个线段中的一个线段是另外两个线段的比例中项．五、（每小题10分，满分20分）19．（10分）如图函数y1＝k1x+b的图象与函数y2＝（x＞0）的图象交于A、B两点，与y轴交于C点．已知A点的坐标为（2，1），C点坐标为（0，3）．（1）求函数y1的表达式和B点坐标；（2）观察图象，比较当x＞0时，y1和y2的大小．20．（10分）如图，在一面靠墙的空地上用长为24米的篱笆，围成中间隔有二道篱笆的长方形花圃，墙的最大可用长度为8米，设花圃的宽AB为x米，面积为S平方米．（1）求S与x的函数关系式；（2）求自变量的取值范围；（3）当x取何值时所围成的花圃面积最大，最大值是多少？六、（本题满分12分）21．（12分）在预防流感期间某住宅小区的活动室坚持天天消毒，下图是某次消毒时活动室内空气中消毒液浓度y（单位：毫克/立方米）随时间x（单位：分钟）的变化情况图．从开始喷药到喷药结束的10分钟内（包括第十分钟），y是x的二次函数；喷药结束后（从第十分钟开始），y是x的反比例函数．（1）如果点A是图中二次函数的顶点，求二次函数和反比例函数的解析式（要写出自变量取值范围）；（2）已知空气中消毒液浓度y不少于15毫克/立方米且持续时间不少于8分钟才能有效消毒，通过计算，请你回答这次消毒是否有效？七.（本题满分12分）22．（12分）如图，抛物线与直线AB交于点A（﹣1，0），B（4，）．点D 是抛物线A，B两点间部分上的一个动点（不与点A，B重合），直线CD与y轴平行，交直线AB于点C，连接AD，BD．（1）求抛物线的解析式；（2）①当D为抛物线顶点时，线段DC的长度是多少？②设点D的横坐标为m，△ADB的面积为S，求S关于m的函数关系式，并求出S的最大值．八.（本题满分14分）23．（14分）农经公司以30元/千克的价格收购一批农产品进行销售，为了得到日销售量p （千克）与销售价格x（元/千克）之间的关系，经过市场调查获得部分数据如下表：销售价格x（元/千克）3035404550日销售量p（千克）6004503001500（1）请你根据表中的数据，用所学过的一次函数、二次函数、反比例函数的知识确定p 与x之间的函数表达式；（2）农经公司应该如何确定这批农产品的销售价格，才能使日销售利润最大？（3）若农经公司每销售1千克这种农产品需支出a元（a＞0）的相关费用，当40≤x≤45时，农经公司的日获利的最大值为2430元，求a的值．（日获利＝日销售利润﹣日支出费用）参考答案一、选择题1．解：A、＝⇒＝，故正确；B、＝4⇒＝4，故正确；C、＝⇒＝﹣，故错误；D、＝⇒＝，故正确．故选：C．2．解：设y＝，∵当x＝3时，y＝4，∴4＝，解得，k＝12，∴y＝，当x＝4时，y＝＝3，故选：B．3．解：根据黄金分割的概念得：b＝a＝5（﹣1）．故选：B．4．解：根据：比例尺＝图上距离：实际距离，设实际距离为xcm，得：1：10000＝2：x，∴相距2cm的两地的实际距离是2×10000＝20000（cm）＝200（m），故选：C．5．解：根据题意，设二次函数的表达式为y＝ax2+bx+c，抛物线过（﹣1，0），（0，2），（2，0），所以，解得a＝﹣1，b＝1，c＝2，这个二次函数的表达式为y＝﹣x2+x+2．故选：A．6．解：由矩形的面积公式可得xy＝6，∴y＝（x＞0，y＞0）．图象在第一象限．故选：C．7．：∵点A（﹣3，y1）、B（﹣2，y2）、C（3，y3）都在反比例函数y＝的图象上，∴y1＝﹣；y2＝﹣2；y3＝，∵＞﹣＞﹣2，∴y3＞y1＞y2．故选：D．8．解：y＝x2﹣2x+1＝（x﹣1）2中a＝1＞0，开口向上，顶点坐标为（1，0），对称轴为x ＝1，当x＞1时，y随着x的增大而增大．故选：D．9．解：二次函数y＝ax2+bx+c的图象开口向下可知a＜0，对称轴位于y轴左侧，a、b同号，即b＜0．图象经过y轴正半可知c＞0，根据对称轴和一个交点坐标用a表示出b，c，b ＝2a，c＝﹣3a，确定一次函数和反比例函数有2个交点，由a＜0，b＜0可知，直线y＝ax﹣2b经过一、二、四象限，由c＞0可知，反比例函数y＝的图象经过第一、三象限，故选：C．10．解：∵抛物线的对称轴为直线x＝﹣＝﹣2，∴4a﹣b＝0，所以①正确；∵与x轴的一个交点在（﹣3，0）和（﹣4，0）之间，∴由抛物线的对称性知，另一个交点在（﹣1，0）和（0，0）之间，∴抛物线与y轴的交点在y轴的负半轴，即c＜0，故②正确；∵由②知，x＝﹣1时y＞0，且b＝4a，即a﹣b+c＝a﹣4a+c＝﹣3a+c＞0，所以③正确；由函数图象知当x＝﹣2时，函数取得最大值，∴4a﹣2b+c≥at2+bt+c，即4a﹣2b≥at2+bt（t为实数），故④错误；∵抛物线的开口向下，且对称轴为直线x＝﹣2，∴抛物线上离对称轴水平距离越小，函数值越大，∴y1＜y3＜y2，故⑤错误；故选：B．二、填空题（每小题5分，共20分）11．解：设反比例函数的表达式是y＝（k≠0），＝|k|＝6，由题意知，S矩形PEOF所以k＝±6，又因为反比例函数图象在第二象限上，k＜0，所以k＝﹣6，即反比例函数的表达式是y＝﹣，故答案为y＝﹣．12．解：如图，建立平面直角坐标系，设横轴x通过AB，纵轴y通过AB中点O且通过C点，则通过画图可得知O为原点，抛物线以y轴为对称轴，且经过A，B两点，OA和OB可求出为AB的一半2米，抛物线顶点C坐标为（0，2），通过以上条件可设顶点式y＝ax2+2，其中a可通过代入A点坐标（﹣2，0），到抛物线解析式得出：a＝﹣0.5，所以抛物线解析式为y＝﹣0.5x2+2，当水面下降1米，通过抛物线在图上的观察可转化为：当y＝﹣1时，对应的抛物线上两点之间的距离，也就是直线y＝﹣1与抛物线相交的两点之间的距离，可以通过把y＝﹣1代入抛物线解析式得出：﹣1＝﹣0.5x2+2，解得：x＝±，所以水面宽度增加到2米，故答案为：2米．13．解：∵DE∥BC，EF∥AB，∴四边形BDEF为平行四边形，∴DE＝BF，BD＝EF，∵EF∥AB，∴；所以①正确；∵DE∥BC，∴△ADE∽△ABC，∴＝，而DE＝BF，∴＝；所以②正确；∵EF＝BD，而AD≠BD，∴不成立，所以③错误；∵EF∥AB，∴＝；即＝所以④正确．14．解：由二次函数y＝x2﹣2mx（m为常数），得到对称轴为直线x＝m，抛物线开口向上，当m≥2时，由题意得：当x＝2时，y最小值为﹣2，代入得：4﹣4m＝﹣2，即m＝1.5＜2，不合题意，舍去；当﹣1≤m≤2时，由题意得：当x＝m时，y最小值为﹣2，代入得：﹣m2＝﹣2，即m＝或m＝﹣（舍去）；当m＜﹣1时，由题意得：当x＝﹣1时，y最小值为﹣2，代入得：1+2m＝﹣2，即m＝﹣1.5，综上，m的值是﹣1.5或，故答案为：﹣1.5或三、解答题（本大题共有2小题，每小题8分，满分16分）15．解：∵AB＝AC，∴＝，∴＝，∵l1∥l2∥l3，∴＝，∵DF＝9，∴＝＝，解得：EF＝．16．解：（1）由题意可得出：y＝x2﹣2x+1＝（x﹣1）2，∴此函数图象的顶点坐标为：（1，0）；（2）①由题意可得出：y＝x2+4x﹣1＝（x+2）2﹣5，∴将此函数的图象先向右平移1个单位，再向上平移1个单位后得到：y＝（x+2﹣1）2﹣5+1＝（x+1）2﹣4＝x2+2x﹣3，∴图象对应的函数的特征数为：[2，﹣3]；②∵一个函数的特征数为[2，3]，∴函数解析式为：y＝x2+2x+3＝（x+1）2+2，∵一个函数的特征数为[3，4]，∴函数解析式为：y＝x2+3x+4＝（x+）2+，∴原函数的图象向左平移个单位，再向下平移个单位得到．四、（本大题共有2小题，每小题8分，满分16分）17．解：①当m2﹣1＝0，且2m+2≠0，即m＝1时，该函数是一次函数，则其图象与x轴只有一个公共点；②当m2﹣1≠0，即m≠±1时，该函数是二次函数，则△＝（2m+2）2﹣8（m2﹣1）＝0，解得m＝3，m＝﹣1（舍去）．综上所述，m的值是1或3．18．解：（1）设a＝3k，b＝2k，c＝6k，∵a+2b+c＝133k+2×2k+6k＝13∴k＝1所以a＝3，b＝2，c＝6；（2）∵设另外一条线段为x，若x为比例中项，可得若a为比例中项，可得若c为比例中项，可得c2＝ax，x＝12；综上所述：或或12．五、（本大题共有2小题，每小题10分，满分20分）19．解：（1）由题意，得，解得，∴y1＝﹣x+3又∵A点在函数上，∴，解得k2＝2，∴，解方程组，得，所以点B的坐标为（1，2）；（2）当0＜x＜1或x＞2时，y1＜y2；当1＜x＜2时，y1＞y2；当x＝1或x＝2时，y1＝y2．20．解：（1）设花圃的宽AB为x米，则BC＝（24﹣4x）m，根据题意得出：S＝x（24﹣4x）＝﹣4x2+24x；（2）∵墙的可用长度为8米∴0＜24﹣4x≤8解得：4≤x＜6；（3）S＝﹣4x2+24x＝﹣4（x2﹣6x）＝﹣4（x﹣3）2+36，∵4≤x＜6，∴当x＝4m时，S＝32平方米．最大值六、（本题满分12分）21．解：（1）依题意可知，A（10，20）为抛物线顶点，设二次函数解析式为y＝a（x﹣10）2+20，把O（0，0）代入，得100a+20＝0，a＝﹣，所以，二次函数解析式为y＝﹣（x﹣10）2+20（0≤x≤10），设反比例函数关系式为y＝，将A点坐标代入，得k＝xy＝200，所以，反比例函数关系式为y＝（x＞10）；（2）把y＝15代入y＝﹣（x﹣10）2+20中，得＝﹣（x﹣10）2+20＝15，解得x＝5或x＝15（舍去），把y＝15代入y＝中，得x＝13，而13﹣5＝8＞8，所以，这次消毒有效．七.（本题满分12分）22．解：（1）由题意得解得：故抛物线解析式为：y＝﹣x2+2x+；（2）①∵y＝﹣x2+2x+＝﹣（x﹣2）2+，∴顶点设直线AB为：y＝kx+b，则有解得∴直线解析式为：，当x＝2时，y＝×2+＝，∴∴，②由题意可得：D（m，），C（m，），CD＝（）﹣（）＝．∴＝×CD＝×（）＝﹣m2+m+5＝﹣（m﹣）2+．∵，∴当时，S最大值为．八.（本题满分14分）23．解：（1）假设p与x成一次函数关系，设函数关系式为p＝kx+b，则，解得：k＝﹣30，b＝1500，∴p＝﹣30x+1500，检验：当x＝35，p＝450；当x＝45，p＝150；当x＝50，p＝0，符合一次函数解析式，∴所求的函数关系为p＝﹣30x+1500；（2）设日销售利润w＝p（x﹣30）＝（﹣30x+1500）（x﹣30）即w＝﹣30x2+2400x﹣45000，∴当x＝﹣＝40时，w有最大值3000元，故这批农产品的销售价格定为40元，才能使日销售利润最大；（3）日获利w＝p（x﹣30﹣a）＝（﹣30x+1500）（x﹣30﹣a），即w＝﹣30x2+（2400+30a）x﹣（1500a+45000），对称轴为x＝﹣＝40+a，①若a＞10，则当x＝45时，w有最大值，即w＝2250﹣150a＜2430（不合题意）；②若a＜10，则当x＝40+a时，w有最大值，将x＝40+a代入，可得w＝30（a2﹣10a+100），当w＝2430时，2430＝30（a2﹣10a+100），解得a1＝2，a2＝38（舍去），综上所述，a的值为2．。

2018~2019 学年五十中东区九年级（上）期中物理试卷总分：100 分考试时间：60 分钟注意事项：1．答题前填写好自己的姓名、班级、考号等信息2．请将答案正确填写在答题卡上3．本试卷中g=10N/kg一、填空题(每空2 分，共32 分)1.如表是研究摩擦起电时得出的物体带电次序，表中任何两种物体相互摩擦时，次序在前的带正电，次序在后的带负电。

由表中可知玻璃与石棉摩擦后,石棉将带___电.(正/负),玻璃对电子的束缚能力要比尼龙.(强/弱)2.将丝绸摩擦过的玻璃棒去接触不带电的验电器的金属球,再靠近另一个完全相同验电器乙的金属球,则甲、乙两验电器内出现的瞬间电流的方向_____________,甲、乙验电器的金属球带____________电荷。

（两空都选填“相同”或“不同”）3. 某些高山上的积雪终年不化，因为大气压强随海拔高度的增加而减小，使得冰雪的熔点____________（选填“高于0 度”或“低于0 度”），还有山顶上堆满冰雪后，由于冰雪表面反射阳光的作用强，照射到这里的阳光，一般有50%~~90%的光被反射回去，使得这里气温更低。

从酒精和水的混合物中分离出酒精,其原理是利用酒精和水的___________不同.4.完全相同的甲乙两烧杯中装有质量和初温相同的同种液体，分别用两个不同的加热器A、B 加热（不计各种热量损失），加热过程中温度变化如图a。

如果仍用这两个加热器分别给完全相同的丙、丁两烧杯中质量和初温相同的不同液体加热，加热过程中温度变化如图b 所示，则丙烧杯中液体比热容__________丁烧杯中液体的比热容（选填“大于”、“小于”或等于）.5.如图是简化了的电冰箱的电路图.图中M 是压缩机的电动机,L 是电冰箱内部的照明灯.当电冰箱接入电路后,关闭了电冰箱的门时,开关S1 与S2 的状态是______________ ;当又打开正在工作的电冰箱门时,开关S1 与S2 的状态是________________．6.如图,活塞将气缸分成甲、乙两气室、活塞(连同拉杆)是绝热的,且不漏气,以、分别表示甲、乙两气室中气体的内能,则在将拉杆缓慢向外拉的过程中 E 甲和 E 乙的变化情况分别是: ______________,_____________.(填“变大”“变小”或“不变”)7.小明乘公交车上学,善于观察的他发现:在寒冷的冬天,在开有空调的公交车玻璃窗上会有小水滴附着在上面,小水珠附着在玻璃的__________________(选填“内表面” 或“外表面”).8.如果导体两端的电压是1V,通过的电流是1A,那么这段导体的电阻就是.对于这段导体来说,当通过它的电流是2A 时,它对电流的阻碍作用_______________ (填“变大”、“变小”或“不变”)；当它两端的电压是4V 时,它的电阻是______________Ω．9. 经验表明, 自制家用太阳能热水器的效率在夏天可达50％; 从太阳能手册中查到, 在地球表面, 晴天时垂直于阳光的表面接收到的热辐射为 1.26×103J/m2 如果晒水箱内的水大约有40 千克, 晒水箱接收阳光垂直照射的面积始终是1.6 m2, 要使水温上升30℃需要__________秒.10.熔化热是指单位质量的晶体熔化成同温度的液态物质所需要的热量.通常情况下冰的熔化热是3.35x103J/kg.现给零摄氏度的冰加热,直至沸腾.(设环境为通常状况)求冰熔化成水,直至沸腾至少所需的热量_________________.二、选择题(每题3 分，共30 分)11. 关于物态变化的说法正确的是( )A.夏天,我们看到冰糕冒的“白气”是蒸发现象B.把糖放入水中,水变甜是熔化现象C.秋天,窗户玻璃表面形成的水雾是液化现象D.长时间使用的冰箱,冷冻室内壁容易结冰是凝固现象12.如图所示的电路中,S 闭合时小灯泡L1、L2 正常发光.若将电压表和电流表的位置对换,则( ) A小灯泡L1 会被烧坏B小灯泡L1 不会发光C电流表示数不变D电压表示数不变13.将手帕放在酒精的溶液中,待均匀湿透后取出,用镊子夹住两角展开,用火点燃,当手帕上的火焰熄灭后,手帕完好无损(如图所示).对于这一现象,下面解释正确的是( )A.这是魔术,你所看到的是一种假象B.火焰的温度低于棉布的着火点C.酒精燃烧后使棉布的着火点升高D.手帕上的水汽化吸热,使手帕的温度低于棉布的着火点14. 如图所示，在“探究串联电路的电压规律”的实验时，闭合开关，用电压表分别测出两AB,BC,AC,端的电压分别为U AB=1.2V、U BC=1.8V、U AC=3V,在表格中记录数据后，接着的实验步骤是（）A.整理数据，结束实验B.分析数据，得出结论C.换用不同规格的小灯泡，再测出几组电压值D.换用电压表的另一量程，再测出一组电压值15. 如图所示是滑动变阻器的结构和连入电路的示意图,当滑片P 向右滑动时,连入电路的电阻变小的是( )A. B. C. D.16.质量相同的水和铜块，吸收相等的热量后，则下列说法正确的是（）A 铜块和水的温度变化相同B 铜块和水的内能变化相同C 若将铜块投入水中，则铜块放热，水吸热D 将铜块投入水中，则铜块和水之间不发生热传递17.新交通法规于2013 年1 月1 日施行,驾驶员不系安全带记3 分,罚100 元。

2018-2019学年安徽省合肥五十中东校区九年级（上）期中数学试卷一、选择题（每题4分，共40分）1．（4分）下列二次函数的图象，不能通过函数y＝3x2的图象平移得到的是（）A．y＝3x2+2B．y＝3（x﹣1）2C．y＝3（x﹣1）2+2D．y＝2x22．（4分）下列四组线段中，不是成比例线段的是（）A．a＝3 b＝6 c＝2 d＝4B．a＝1 b＝c＝d＝2C．a＝4 b＝6 c＝5 d＝10D．a＝2 b＝c＝d＝23．（4分）若抛物线y＝x2﹣2x+c与y轴的交点为（0，﹣3），则下列说法不正确的是（）A．抛物线的开口向上B．抛物线的对称轴是x＝1C．当x＝1时，y的最大值为﹣4D．当x≥2时，y随x增大而增大4．（4分）如图，反比例函数的图象经过点A（2，1），若y≤1，则x的范围为（）A．x≥1B．x≥2C．x＜0或0＜x≤1D．x＜0或x≥25．（4分）如图，△ABC中，P为AB上的一点，在下列四个条件中：①∠ACP＝∠B；②∠APC＝∠ACB；③AC2＝AP•AB；④AB•CP＝AP•CB，能满足△APC和△ACB相似的条件是（）A．①②④B．①③④C．②③④D．①②③6．（4分）如图，反比例函数y＝的图象经过矩形OABC的边AB的中点D，则矩形OABC的面积为（）A．2B．4C．5D．87．（4分）在平面直角坐标系中，已知点A（﹣4，2），B（﹣6，﹣4），以原点O为位似中心，相似比为，把△ABO缩小，则点A的对应点A′的坐标是（）A．（﹣2，1）B．（﹣8，4）C．（﹣8，4）或（8，﹣4）D．（﹣2，1）或（2，﹣1）8．（4分）已知抛物线y＝（x﹣1）2+k上有三点A（﹣2，y1），B（﹣1，y2），C（2，y3），则y1，y2，y3的大小关系为（）A．y1＞y2＞y3B．y3＞y2＞y1C．y2＞y3＞y1D．y2＞y1＞y39．（4分）a≠0，函数y＝与y＝﹣ax2+a在同一直角坐标系中的大致图象可能是（）A．B．C．D．10．（4分）如图所示，已知点E，F分别是△ABC中AC、AB边的中点，BE，CF相交于点G，S△EFG＝1，则四边形BCEF的面积是（）A．7B．8C．9D．10二、填空题（每题5分，共20分）11．（5分）反比例函数的图象在第一、三象限，则m的取值范围是．12．（5分）赵州桥的桥拱是近似的抛物线形，建立如图所示的平面直角坐标系，其函数关系式为y＝﹣，当水面离桥拱顶的高度DO是4米时，这时水面宽度AB为米．13．（5分）如图，平面内有16个格点，每个格点小正方形的边长为1，则图中阴影部分的面积为．14．（5分）如图，点A的坐标为（1，1），点C是线段OA上的一个动点（不运动至O，A两点），过点C作CD⊥x轴，垂足为D，以CD为边在右侧作正方形CDEF．连接AF并延长交x轴的正半轴于点B，连接OF，若以B，E，F为顶点的三角形与△OFE相似，B点的坐标是．三、（本大题共2小题，每小题8分，满分16分）15．（8分）已知函数y＝3x2﹣2x﹣1，求出此抛物线与坐标轴的交点坐标．16．（8分）装卸工人往一辆大型运货车上装载货物，装完货物所需时间y（min）与装载速度x（t/min）之间的函数关系如图：（1）求y与x之间的函数关系式；（2）货车到达目的地后开始卸货，如果以1.5t/min的速度卸货，需要多长时间才能卸完货物？四、（本大题共2小题，每小题8分，满分16分）17．（8分）如图所示，小明从路灯下向前走了5米，发现自己在地面上的影子长DE是2米，如果小明的身高是1.6米，那么路灯离地面的高度AB是多少米？18．（8分）如图，已知反比例函数y＝的图象与一次函数y＝kx+b的图象交于点A（1，m），B（n，2）两点．（1）求一次函数的解析式；（2）直接写出不等式≥kx+b的解集．五、（本大题共2小题，每小题10分，满分20分）19．（10分）如图，在同一平面内，将两个全等的等腰直角三角形ABC和AFG摆放在一起，A为公共顶点，∠BAC ＝∠AGF＝90°．AF、AG与边BC的交点分别为D、E（点D不与点B重合，点E不与点C重合）．（1）图中共有对相似而不全等的三角形；（2）选取其中一对进行证明．20．（10分）如图，在直角坐标系中，抛物线经过点A（0，4），B（1，0），C（5，0）（1）求抛物线的解析式和顶点E坐标；（2）该抛物线有一点D，使得S△DBC＝S△EBC，求点D的坐标．六、（本题满分12分）21．（12分）如图是3×5的网格，正方形网格中的每个小正方形边长都是1，每个小格的顶点叫做格点，以格点为顶点的图形叫做格点图．（1）图1中的格点△ABC与△DEF相似吗？请说明理由；（2）请在图2中选择适当的位似中心作△A1B1C1与△ABC位似，且相似比不为1；（3）请在图3中画一个格点△A2B2C2与△ABC相似（注意：△A2B2C2与△ABC、△DEF、△A1B1C1都不全等）．七、（本题满分12分）22．（12分）俄罗斯世界杯足球赛期间，某商店销售一批足球纪念册，每本进价40元，规定销售单价不低于44元，且获利不高于30%．试销售期间发现，当销售单价定为44元时，每天可售出300本，销售单价每上涨1元，每天销售量减少10本，现商店决定提价销售．设每天销售量为y本，销售单价为x元．（1）请直接写出y与x之间的函数关系式和自变量x的取值范围；（2）将足球纪念册销售单价定为多少元时，商店每天销售纪念册获得的利润w元最大？最大利润是多少元？八、（本题满分14分）23．（14分）已知正方形ABCD的对角线AC，BD相交于点O．（1）如图1，E，G分别是OB，OC上的点，CE与DG的延长线相交于点F．若DF⊥CE，求证：OE＝OG；（2）如图2，H是BC上的点，过点H作EH⊥BC，交线段OB于点E，连结DH交CE于点F，交OC于点G．若OE＝OG，①求证：∠ODG＝∠OCE；②当AB＝1时，求HC的长．2018-2019学年安徽省合肥五十中东校区九年级（上）期中数学试卷参考答案与试题解析一、选择题（每题4分，共40分）1．【解答】解：A、y＝3x2的图象向上平移2个单位得到y＝3x2+2，故A选项错误；B、y＝3x2的图象向右平移1个单位得到y＝3（x﹣1）2，故B选项错误；C、y＝3x2的图象向右平移1个单位，向上平移2个单位得到y＝3（x﹣1）2+2，故C选项错误；D、y＝3x2的图象平移不能得到y＝2x2，故D选项正确．故选：D．2．【解答】解：A、3×4＝6×2，是成比例线段，故本选项错误；B、1×2＝×，是成比例线段，故本选项错误；C、4×10≠6×5，不是成比例线段，故本选项正确；D、2×＝×2，是成比例线段，故本选项错误．故选：C．3．【解答】解：把（0，﹣3）代入y＝x2﹣2x+c中得c＝﹣3，抛物线为y＝x2﹣2x﹣3＝（x﹣1）2﹣4，所以：抛物线开口向上，对称轴是x＝1，当x＝1时，y的最小值为﹣4，当x≥2时，y随x增大而增大观察选项，B选项符合题意．故选：C．4．【解答】解：在第一象限纵坐标为1的以及小于1的函数图象所对应的自变量的取值为x≥2；在第三象限纵坐标为1的以及小于1的函数图象所对应的自变量的取值为x＜0．故选：D．5．【解答】解：当∠ACP＝∠B，∠A公共，所以△APC∽△ACB；当∠APC＝∠ACB，∠A公共，所以△APC∽△ACB；当AC2＝AP•AB，即AC：AB＝AP：AC，∠A公共，所以△APC∽△ACB；当AB•CP＝AP•CB，即＝，而∠P AC＝∠CAB，所以不能判断△APC和△ACB相似．故选：D．6．【解答】解：∵y＝，∴OA•AD＝2．∵D是AB的中点，∴AB＝2AD．∴矩形的面积＝OA•AB＝2AD•OA＝2×2＝4．故选：B．7．【解答】解：∵点A（﹣4，2），B（﹣6，﹣4），以原点O为位似中心，相似比为，把△ABO缩小，∴点A的对应点A′的坐标是：（﹣2，1）或（2，﹣1）．故选：D．8．【解答】解：因为a＝＞0，开口向上，在对称轴的左侧，y随x的增大而减小，根据二次函数图象的对称性可知，C（2，y3）和（0，y3）关于直线x＝1对称，因为﹣2＜﹣1＜0，故y1＞y2＞y3，故选：A．9．【解答】解：当a＞0时，函数y＝的图象位于一、三象限，y＝﹣ax2+a的开口向下，交y轴的正半轴，没有符合的选项，当a＜0时，函数y＝的图象位于二、四象限，y＝﹣ax2+a的开口向上，交y轴的负半轴，D选项符合；故选：D．10．【解答】解：∵点E，F分别是AC、AB边的中点，∴EF∥BC，EF＝BC，∴△EFG∽△BCG，∴＝＝，＝（）2＝，∴S△BGF＝2S△EFG＝2，S△CGE＝S△EFG＝2，S△BGC＝4S△EFG＝4，∴四边形BCEF的面积＝1+2+2+4＝9，故选：C．二、填空题（每题5分，共20分）11．【解答】解：∵反比例函数的图象在第一、三象限，∴m﹣1＞0，解得m＞1．故答案为：m＞1．12．【解答】解：当y＝﹣4时，﹣4＝﹣，解得，x1＝﹣10，x2＝10，∴当水面离桥拱顶的高度DO是4米时，这时水面宽度AB为：10﹣（﹣10）＝20（米），故答案为：20．13．【解答】解：如图，∵GF∥HC，∴△AGF∽△AHC，∴＝＝，∴GF＝HC＝，∴OF＝OG﹣GF＝2﹣＝．同理MN＝，则有OM＝．∴S△OFM＝××＝，∴S阴影＝1﹣＝．故答案为：．14．【解答】解：过点A作AH⊥OB，∵点A的坐标为（1，1），∴AH＝OH＝1，∠AOB＝45°，∴OD＝CD，设CF＝x，∵四边形CDEF是正方形，∴CF∥DE，CD＝CF＝EF＝DE，∴CD＝CF＝EF＝DE＝x，∴OE＝OD+DE＝2EF，∵以B，E，F为顶点的三角形与△OFE相似，∴①EF＝2EB，则EB＝x，∴OB＝OE+EB＝2x+x＝x，∵CF∥DE，∴△ACF∽△AOB，∴＝，即＝1﹣x，解得x＝，OB＝×＝，∴点B的坐标为（，0），②EB＝2EF时，则EB＝2x，∴OB＝OE+EB＝2x+2x＝4x，∵CF∥DE，∴△ACF∽△AOB，∴＝，即＝1﹣x，解得x＝，OB＝4x＝4×＝3，∴点B的坐标为（3，0）．③如图当点B在点E左边时，设正方形的边长为x，∵△OEF∽△FEB，∴OE：EF＝EF：BE＝2：1，∴BE＝x，OB＝x，∵＝，∴＝，∴x＝，∴OB＝，∴B（，0），综上所述，点B的坐标是（，0）或（3，0）或（，0）．故答案为：（，0）或（3，0）或（，0）．三、（本大题共2小题，每小题8分，满分16分）15．【解答】解：∵函数y＝3x2﹣2x﹣1，∴当y＝0时，0＝3x2﹣2x﹣1＝（3x+1）（x﹣1），解得，x1＝﹣，x2＝1，当x＝0时，y＝﹣1，∴此抛物线与坐标轴的交点坐标是（﹣，0），（1，0），（0，﹣1）．16．【解答】解：（1）x（t/min）代表装载速度，y（min）代表装完货物所需时间，货物的质量m＝xy，把（0.5，40）代入得货物的质量m＝0.5×40＝20；由xy＝20得；（2）当x＝1.5时，．需要分钟时间才能卸完货物四、（本大题共2小题，每小题8分，满分16分）17．【解答】解：由图知，DE＝2米，CD＝1.6米，AD＝5米，∴AE＝AD+DE＝5+2＝7米∵CD∥AB，∴△ECD∽△EBA∴即∴米．答：路灯离地面的高度AB是5.6米．18．【解答】解：（1）把点A（1，m），B（n，2），分别代入得m＝6，2n＝6，解得n＝3，∴A点坐标为（1，6），B点坐标为（3，2），把A（1，6），B（3，2）分别代入y＝kx+b得，解得，∴一次函数解析式为y＝﹣2x+8；（2）不等式≥kx+b的解集是0＜x≤1或x≥3．五、（本大题共2小题，每小题10分，满分20分）19．【解答】解：（1）图中共有相似而不全等的三角形：△ABE∽△DAE，△ABE∽△DCA，△DAE∽△DCA3对；（2）∵△ABC与△GAF是等腰直角三角形，∴∠B＝∠GAF＝∠C＝90°，∵∠AEB＝∠DEA，∴△ABE∽△DAE，∵∠ADC＝∠EDA，∠DAE＝∠C＝45°，∴△DAE∽△DCA，∴∠DAC＝∠DEA，∠B＝∠C，∴△DAE∽△DCA．20．【解答】解：（1）由题意，设y＝a（x﹣1）（x﹣5），代入A（0，4），得，∴，∴，故顶点E坐标为；（2）∵S△DBC＝S△EBC，∴两个三角形在公共边BC上的高相等，又点E到BC的距离为，∴点D到BC的距离也为，则（x﹣3）2﹣＝，解得x＝3±2，则点D或．六、（本题满分12分）21．【解答】解：（1）相似，理由如下：∵，∴，故相似（2）如图2所示：（3）如图3所示：七、（本题满分12分）22．【解答】解：（1）由题意得：y＝﹣10x+740（≤x≤52），（2）w＝（x﹣40）（﹣10x+740）＝（x﹣57）2+2890，当x＜57时，w随x的增大而增大，而44≤x≤52，所以当x＝52时，w有最大值，最大值为2640，答：将足球纪念册销售单价定为52元时，商店每天销售纪念册获得的利润w元最大，最大利润2640元．八、（本题满分14分）23．【解答】（1）证明：如图1中，∵四边形ABCD是正方形，∴AC⊥BD，OD＝OC，∴∠DOG＝∠COE＝90°，∴∠OEC+∠OCE＝90°，∵DF⊥CE，∴∠OEC+∠ODG＝90°，∴∠ODG＝∠OCE，∴△DOG≌△COE（ASA），∴OE＝OG．（2）①证明：如图2中，∵AC，BD为对角线，∴OD＝OC，∵OG＝OE，∠DOG＝∠COE＝90°，∴△ODG≌△OCE，∴∠ODG＝∠OCE．②解：设CH＝x，∵四边形ABCD是正方形，AB＝1，∴BH＝1﹣x，∠DBC＝∠BDC＝∠ACB＝45°，∵EH⊥BC，∴∠BEH＝∠EBH＝45°，∴EH＝BH＝1﹣x，∵∠ODG＝∠OCE，∴∠BDC﹣∠ODG＝∠ACB﹣∠OCE，∴∠HDC＝∠ECH，∵EH⊥BC，∴∠EHC＝∠HCD＝90°，∴△CHE∽△DCH，∴＝，∴HC2＝EH•CD，∴x2＝（1﹣x）•1，解得x＝或（舍弃），∴HC＝．。

2021-2022学年安徽省合肥五十中新校九年级（上）开学数学试卷1. 下列二次根式中，最简二次根式的是( )A. √15 B. √0.5 C. √5 D. √502. 如果一个多边形的每一个外角都是40∘，那么这个多边形的内角和是( )A. 540∘B. 720∘C. 1080∘D. 1260∘ 3. 下列长度的三条线段能组成直角三角形的是( )A. 1，√2，3B. 10，15，20C. √7，3，4D. 2，3，44. 某农科院对甲、乙两种甜玉米各用10块相同条件的试验田进行试验，得到两个品种每公顷产量的两组数据，其方差分别为s 甲2=0.002、s 乙2=0.03，则( )A. 甲比乙的产量稳定B. 乙比甲的产量稳定C. 甲、乙的产量一样稳定D. 无法确定哪一品种的产量更稳定5. 如图，DE 是△ABC 的中位线，直角∠AFB 的顶点在DE 上，AB =5，BC =8，则EF 的长为( )A. 1B. 1.5C. 2D. 不能确定6. 已知二次函数y =−x 2−2x +3，下列叙述中正确的是( )A. 图象的开口向上B. 图象的对称轴为直线x =1C. 函数有最小值D. 当x >−1时，函数值y 随自变量x 的增大而减小7. 某中学初四学生毕业时，每个同学都给其他同学写了一份毕业留言，全班共写了纪念留言1640份，则全班共有学生名.( )A. 39B. 40C. 41D. 428. 若直角三角形的两边长分别是方程x 2−7x +12=0的两根，则该直角三角形的面积是( )A. 6B. 12C. 12或3√72D. 6或3√729. 已知二次函数y =−x 2+(2m −1)x −3，当x >1时，y 随x 的增大而减小，而m 的取值范围是( )A. m≤12B. m<−12C. m>32D. m≤3210.如图，在正方形ABCD中，AB=4，E为对角线AC上与A，C不重合的一个动点，过点E作EF⊥AB于点F，EG⊥BC于点G，连接DE，FG，下列结论：①DE=FG；②DE⊥FG；③∠BFG=∠ADE；④FG的最小值为3.其中正确结论的个数有( )A. 1个B. 2个C. 3个D. 4个11.若式子√x−2x−3有意义，则x的取值范围为______.12.将抛物线y=−13x2+1向上平移2个单位后，得到的新抛物线与y轴交点的坐标为______.13.若关于x的一元二次方程ax2−4x+6=0有实数根，则整数a的最大值是______.14.如图，在三角形ABC中，AB=3，BC=3√3.AC=6，点D是AC上一个动点，过点D作DF⊥BC于点F，过点F作FE//AC，交AB于点E.(1)当四边形ADFE为菱形时，则∠AED______.(2)当△DEF为直角三角形时，则CD=______.15.计算：(√2−√13)÷√3−(√2−√3)2.16.解方程：x(2x−4)=5−8x.17.如图：四边形ABCD中，AB=BC=√2，DA=1，CD=√5，且AB⊥CB于B.试求：(1)∠BAD的度数；(2)四边形ABCD的面积．18.如图，在平面直角坐标系中，点A的坐标为(1,3)，点B的坐标为(1,1).在第一象限内有以AB为底的等腰△ABC，且腰长为√10.(1)在图中画出△ABC，并写出点C的坐标：(2)在x轴上找一点D，使得点A、B、C、D围成一个平行四边形，在图中画该四边形，并写出点D坐标．19.某超市经销一种销售成本为每件20元的商品，据市场调查分析，如果按每件30元销售，一周能售出500件，若销售单价每涨1元，每周销售量就减少10件.设销售单价为每件x元(x≥30)，一周的销售量为y件.(1)直接写出y与x的函数关系式；(2)在超市对该种商品投入不超过5000元的情况下，使得一周销售利润达到8000元，销售单价应定为多少？20.如图，在△ABC中，点O是AC边上的一个动点，过点O作直线MN//BC，设MN交∠BCA的角平分线于点E，交∠BCA的外角平分线于点F.(1)求证：EO=FO；(2)当点O运动到何处时，四边形AECF是矩形？并证明你的结论．21.王大伯承包了一个鱼塘，投放了4000条某种鱼苗，经过一段时间的精心喂养，存活率大致达到了90%，他近期想出售鱼塘里的这种鱼．为了估计鱼塘里这种鱼的总质量，王大伯随机捕捞了20条鱼，分别称得其质量后放回鱼塘，现将这20条鱼的质量作为样本，统计结果如图所示．(1)这20条鱼质量的中位数是______，众数是______.(2)求这20条鱼质量的平均数；(3)经了解，近明市场上这种位的售价为每千克20元，请利用这个样本的平均数．估计王大伯近期售完鱼塘里的这种鱼可收入多少元？x2+bx+c经过点A(3√3,0)和点B(0,3)，且这个抛物线的对称轴为直线l，顶22.抛物线y=−13点为C.(1)求抛物线的解析式；(2)连接AB、AC、BC，求△ABC的面积．23.如图，△ABC中，D是AB上一点，DE⊥AC于点E，F是AD的中点，FG⊥BC于点G，与DE交于点H，若FG=AF，AG平分∠CAB，连接GE，GD，EF.(1)求证：GE=GD；(2)试探究线段AD、AC，EC之间的数量关系，并证明．(3)若点D为FB中点，判断四边形EFDG是什么四边形？并说明理由．答案和解析1.【答案】C中被开方数是分数，故不是最简二次根式；【解析】解：A、√15B、√0.5中被开方数是分数，故不是最简二次根式；C、√5中被开方数不含分母，不含能开得尽方的因数，故是最简二次根式；D、√50中含能开得尽方的因数，故不是最简二次根式；故选：C.根据最简二次根式的定义解答即可.本题主要考查了最简二次根式的定义，最简二次根式满足：(1)被开方数不含分母；(2)被开方数中不含能开得尽方的因数或因式，满足上述两个条件的二次根式，叫做最简二次根式，否则就不是．2.【答案】D【解析】解：360∘÷40∘=9(边)，(9−2)×180∘=1260∘，故选：D.根据多边形的外角和是360∘求出多边形的边数，再用多边形的内角和公式求出多边形的内角和即可．本题考查了多边形的内角和和外角和，掌握多边形的内角和的公式(n−2)⋅180∘是解题的关键．3.【答案】C【解析】解：A、因为12+(√2)2≠32，所以不能组成直角三角形，故本选项不符合题意；B、因为102+152≠202，所以不能组成直角三角形，故本选项不符合题意；C、因为32+(√7)2=42，所以能组成直角三角形，故本选项符合题意；D、因为22+32≠42，所以不能组成直角三角形，故本选项不符合题意．故选：C.欲求证是否为直角三角形，这里给出三边的长，只要验证两小边的平方和等于最长边的平方即可．此题考查了勾股定理的逆定理，在应用勾股定理的逆定理时，应先认真分析所给边的大小关系，确定最大边后，再验证两条较小边的平方和与最大边的平方之间的关系，进而作出判断．4.【答案】A【解析】【分析】本题考查了方差的意义：方差反映一组数据在其平均数左右的波动大小，方差越大，波动就越大，越不稳定，方差越小，波动越小，越稳定．由s 甲2=0.002、s 乙2=0.03，可得到s 甲2<s 乙2，根据方差的意义得到甲的波动小，比较稳定． 【解答】解：∵s 甲2=0.002、s 乙2=0.03， ∴s 甲2<s 乙2，∴甲比乙的产量稳定． 故选：A.5.【答案】B【解析】解：如图，∵D 为AB 中点，∠AFB =90∘，AB =5， ∴DF =12AB =2.5，∵DE 是△ABC 的中位线，BC =8， ∴DE =4，∴EF =4−2.5=1.5， 故选：B.根据直角三角形斜边上的中线等于斜边的一半可得DF =12AB ，再利用三角形中位线定理可得DE =4，进而可得答案．此题主要考查了直角三角形的性质和三角形中位线定理，三角形的中位线平行于第三边，并且等于第三边的一半．6.【答案】D【解析】解：∵a =−1<0， ∴抛物线开口向下，故A 错误； ∴函数有最大值，故C 错误；∵y =−x 2−2x +3=−(x +1)2+4， ∴抛物线的对称轴为直线x =−1，故B 错误；∴当x >−1时，函数值y 随自变量x 的增大而减小，故D 正确； 故选：D.根据二次函数的性质即可进行判断．本题考查了二次函数的性质，二次函数的最值，熟知二次函数的性质是解题的关键．【解析】解：设全班共有学生x名，则每名学生需写(x−1)份毕业留言，依题意得：x(x−1)=1640，解得：x1=41，x2=−40(不合题意，舍去).故选：C.设全班共有学生x名，则每名学生需写(x−1)份毕业留言，根据全班共写了纪念留言1640份，即可得出关于x的一元二次方程，解之取其正值即可得出结论．本题考查了一元二次方程的应用，找准等量关系，正确列出一元二次方程是解题的关键．8.【答案】D【解析】解：∵x2−7x+12=0，∴x=3或x=4.①当长是4的边是直角边时，该直角三角形的面积是12×3×4=6；②当长是4的边是斜边时，第三边是√42−32=√7，该直角三角形的面积是12×3×√7=3√72.故选：D.先解出方程x2−7x+12=0的两个根为3和4，再分长是4的边是直角边和斜边两种情况进行讨论，然后根据直角三角形的面积公式即可求解．本题考查了一元二次方程的解法，勾股定理，三角形的面积，正确求解方程的两根，能够分两种情况进行讨论是解题的关键．9.【答案】D【解析】解：∵y=−x2+(2m−1)x−3，∴对称轴为x=−2m−1−2=2m−12，∵a=−1<0，∴抛物线开口向下，∴在对称轴右侧y随x的增大而减小，∵当x>1时，y随x的增大而减小，∴2m−12≤1，解得m≤32，故选：D.可先求得抛物线的对称轴，再由条件可求得关于m的不等式，可求得答案．本题主要考查二次函数的性质，由函数的增减性得到关于m的不等式是解题的关键．【解析】解：①连接BE，交FG于点O，如图，∵EF⊥AB，EG⊥BC，∴∠EFB=∠EGB=90∘.∵∠ABC=90∘，∴四边形EFBG为矩形．∴FG=BE，OB=OF=OE=OG.∵四边形ABCD为正方形，∴AB=AD，∠BAC=∠DAC=45∘.在△ABE和△ADE中，{AE=AE∠BAC=∠DAC AB=AD，∴△ABE≌△ADE(SAS).∴BE=DE.∴DE=FG.∴①正确；②∵△ABE≌△ADE，∴∠ABE=∠ADE.由①知：OB=OF，∴∠OFB=∠ABE.∴∠OFB=∠ADE.∵∠BAD=90∘，∴∠ADE+∠AHD=90∘.∴∠OFB+∠AHD=90∘.即：∠FMH=90∘，∴DE⊥FG.∴②正确；③由②知：∠OFB=∠ADE.即：∠BFG=∠ADE.∴③正确；④∵点E 为AC 上一动点，∴根据垂线段最短，当DE ⊥AC 时，DE 最小． ∵AD =CD =4，∠ADC =90∘，∴AC =√AD 2+CD 2=4√2. ∴DE =12AC =2√2.由①知：FG =DE ， ∴FG 的最小值为2√2， ∴④错误．综上，正确的结论为：①②③． 故选：C.①连接BE ，易知四边形EFBG 为矩形，可得BE =FG ；由△AEB ≌△AED 可得DE =BE ，所以DE =FG ；②延长DE ，交FG 于M ，交FB 于点H ，由矩形EFBG 可得OF =OB ，则∠OBF =∠OFB ；由∠OBF =∠ADE ，则∠OFB =∠ADE ；由四边形ABCD 为正方形可得∠BAD =90∘，即∠AHD +∠ADH =90∘，所以∠AHD +∠OFH =90∘，即∠FMH =90∘，可得DE ⊥FG ； ③由②中的结论可得∠BFG =∠ADE ；④由于点E 为AC 上一动点，当DE ⊥AC 时，根据垂线段最短可得此时DE 最小，最小值为2√2，由①知FG =DE ，所以FG 的最小值为2√2；本题主要考查了正方形的性质，垂线段最短，三角形全等的判定与性质，矩形的判定与性质，垂直的定义．根据图形位置的特点通过添加辅助线构造全等是解题的关键，也是解决此类问题常用的方法．11.【答案】x ≥2且x ≠3【解析】解：若式子√x−2x−3有意义，则应满足{x−2≥0x−3≠0，解得：x ≥2且x ≠3， 故答案为：x ≥2且x ≠3.先根据二次根式有意义的条件列出关于x 的不等式，求出x 的取值范围即可． 本题考查的是二次根式有意义的条件，即被开方数大于等于0，此题比较简单．12.【答案】(0,3)【解析】解：∵将抛物线y =−13x 2+1向上平移2个单位后，得到的新抛物线的解析式为：y =−13x 2+3，∴当x=0，则y=3，故得到的新抛物线图象与y轴的交点坐标为：(0,3).故答案为：(0,3).先得到抛物线的平移后的解析式，进而得出x=0时y的值，即可得出图象与y轴的交点坐标．此题主要考查了抛物线的平移以及抛物线解析式的变化规律，熟练应用平移规律是解题关键．13.【答案】−1【解析】解：∵ax2−4x+6=0为一元二次方程，∴a≠0，∵ax2−4x+6=0有实数根，∴Δ=b2−4ac≥0，∴(−4)2−4×a×6=16−24a≥0，∴a≤23，又∵a≠0，∴整数a的最大值为−1.故答案为：−1.根据题干得到a≠0，根据有实数根Δ≥0，求出a的范围，最后求出a的值．本题考查根的判别式，注意二次项系数不为0是关键．14.【答案】60∘3或4.8【解析】解：(1)∵AB=3，BC=3√3.AC=6，∴32+(3√3)2=36=62，∴AB2+BC2=AC2，∴∠ABC=90∘，∴∠C=30∘，∠A=60∘，∵四边形ADFE为菱形，∴∠AEF=180∘−60∘=120∘，∴∠AED=12∠AEF=60∘.故答案为：60∘；(2)讨论：①当∠DFE=90∘时．∵FE//AC，∠C=30∘，∴∠EFB=∠C=30∘，∴∠DFE=180∘−90∘−30∘=60∘≠90∘，∴这种情况不存在，②当∠FDE=90∘时，如图2，∵DF⊥BC，∠B=90∘，∴∠DFC=∠B=90∘，∴DF//AB，∵EF//AC，∴四边形AEFD为平行四边形，∴AE=DF=12CD，∵∠DFC=∠FDE=90∘，∴DE//BC，∴∠ADE=∠C=30∘，∠AED=∠B=90∘，在Rt△ADE中，∠AED=90∘，∠ADE=30∘，∴AE=12AD=12(6−CD)，即12CD=12(6−CD)，解得：CD=3，③当∠DEF=90∘时，如图3，∵EF//AC，∠C=30∘，∴∠EFB=∠C=30∘，∵∠DFC=90∘，∴∠DFE=60∘，∵∠DEF=90∘，∴∠FDE=30∘，∵∠B=90∘，∴∠FEB=60∘，∵∠DEF =90∘，∴∠AED =30∘，∴∠ADE =90∘，∠AED =∠FDE =30∘，∴FD//AE ，∴四边形AEFD 为平行四边形，∴AE =DF =12CD ，在Rt △ADE 中，∠ADE =90∘，∠AED =30∘，∴AD =12AE ，即6−CD =12×12CD ，解得：t =4.8.综上所述，当△FED 是直角三角形时，t 的值为3或4.8.故答案为：3或4.8.(1)根据勾股定理逆定理可得∠ABC =90∘，利用菱形的性质即可得出答案；(2)利用分类讨论结合①当∠DFE =90∘时．②当∠FDE =90∘时，③当∠DEF =90∘时，分别分析得出符合题意的答案．此题属于四边形综合题，主要考查了平行四边形的性质以及直角三角形的性质、菱形的判定等知识，根据题意结合分类讨论得出当△FED 是直角三角形时求出CD 的值是解题关键．15.【答案】解：(√2−√13)÷√3−(√2−√3)2=√23−√19−(2−2√6+3) =√63−13−5+2√6 =−163+73√6. 【解析】根据二次根式的除法和完全平方公式，可以将题目中的式子展开，然后合并同类二次根式即可．本题考查二次根式的混合运算，解答本题的关键是明确二次根式混合运算的计算方法．16.【答案】解：方程化为2x 2+4x −5=0，a =2，b =4，c =−5，Δ=b 2−4ac =42−4×2×(−5)=56>0，方程有两个不等的实数根，∴x =−b±√b 2−4ac 2a =−4±√562×2=−4±2√144=−2±√142， 即x 1=−2+√142，x 2=−2−√142.【解析】将一元二次方程整理成一般形式，然后利用公式法解方程．本题考查公式法解一元二次方程，掌握公式法解一元二次方程的步骤是解题关键．17.【答案】解：(1)如图，连接AC.∵AB =BC =√2，∠B =90∘，∴AC =√AB 2+BC 2=2，∠BAC =∠ACB =45∘，∵AD =1，CD =√5，∴AD 2+AC 2=CD 2，∴∠CAD =90∘，∴∠BAD =∠BAC +∠CAD =45∘+90∘=135∘.(2)S 四边形ABCD =S △ABC +S △ADC =12⋅AB ⋅BC +12⋅AD ⋅AC =12×√2×√2+12×1×2=2.【解析】(1)连接AC ，利用勾股定理求出AC ，再利用勾股定理的逆定理证明∠CAD =90∘，可得结论．(2)根据S 四边形ABCD =S △ABC +S △ADC ，求解即可．本题考查勾股定理的逆定理，勾股定理等知识，解题的关键是熟练掌握勾股定理以及逆定理，属于中考常考题型．18.【答案】解：(1)△ABC 如图所示，C(4,2)；(2)四边形如图所示，D(4,0).【解析】(1)利用等腰三角形性质得到C 点在直线y =2上，然后利用腰长为√10确定C 点位置；(2)根据平行四边形的性质即可得到结论．本题考查了平行四边形的性质，等腰三角形的性质，正确地作出图形是解题的关键．19.【答案】解：(1)依题意得：y=500−10(x−30)=−10x+800(x≥30).(2)依题意得：(x−20)(−10x+800)=8000，整理得：x2−100x+2400=0，解得：x1=40，x2=60.当x=40时，20(−10x+800)=8000(元)，8000>5000，不合题意，舍去；当x=60时，20(−10x+800)=4000(元)，4000<5000，符合题意．答：销售单价应定为60元．【解析】(1)根据一周的销售量=500−10×单价上涨的金额，即可得出y与x的函数关系式；(2)利用一周的销售利润=每件的销售利润×一周的销售量，即可得出关于x的一元二次方程，解之即可得出x的值，再结合超市对该种商品投入不超过5000元，即可确定结论．本题考查了一元二次方程的应用以及一次函数的应用，解题的关键是：(1)根据各数量之间的关系，找出y与x的函数关系式；(2)找准等量关系，正确列出一元二次方程．20.【答案】(1)证明：∵CE平分∠ACB，∴∠1=∠2，又∵MN//BC，∴∠1=∠3，∴∠3=∠2，∴EO=CO，同理，FO=CO，∴EO=FO.(2)解：当点O运动到AC的中点时，四边形AECF是矩形．理由：∵EO=FO，点O是AC的中点．∴四边形AECF是平行四边形，∵CF平分∠BCA的外角，∴∠4=∠5，又∵∠1=∠2，∴∠2+∠4=12×180∘=90∘.即∠ECF=90∘，∴四边形AECF是矩形．【解析】(1)根据平行线性质和角平分线性质，以及由平行线所夹的内错角相等易证．(2)根据矩形的判定方法，即一个角是直角的平行四边形是矩形可证．本题涉及矩形的判定定理，解答此类题的关键是要突破思维定势的障碍，运用发散思维，多方思考，探究问题在不同条件下的不同结论，挖掘它的内在联系，向“纵、横、深、广”拓展，从而寻找出添加的条件和所得的结论．21.【答案】1.451.5【解析】解：(1)∵这20条鱼质量的中位数是第10、11个数据的平均数，且第10、11个数据分别为1.4、1.5，∴这20条鱼质量的中位数是1.4+1.52=1.45(kg)，众数是1.5kg.故答案为：1.45，1.5；(2)x−=1.2×1+1.3×4+1.4×5+1.5×6+1.6×2+1.7×220=1.45(kg).故这20条鱼质量的平均数为1.45kg；(3)20×1.45×4000×90%=104400(元).答：估计王大伯近期售完鱼塘里的这种鱼可收入104400元．(1)根据中位数和众数的定义求解可得；(2)利用加权平均数的定义求解可得；(3)用单价乘(2)中所得平均数，再乘存活的数量，从而得出答案．本题考查了用样本估计总体、加权平均数、众数及中位数的知识，解题的关键是正确的用公式求得加权平均数，难度不大．22.【答案】解：(1)∵抛物线y=−13x2+bx+c经过A(3√3,0)、B(0,3)，∴{−9+3√3b+c=0 c=3由上两式解得b=2√33，∴抛物线的解析式为：y=−13x2+2√33x+3；(2)由(1)抛物线对称轴为直线x=√3，把x=√3代入，y=−13x2+2√33x+3得y=4，则点C坐标为(√3,4)，设线段AB所在直线为：y=kx+b，解得AB解析式为：y=−√33x+3，∵线段AB所在直线经过点A(3√3,0)、B(0,3)，抛物线的对称轴l与直线AB交于点D，∴设点D的坐标为D(√3,m)，将点D(√3,m)代入y=−√33x+3，解得m=2，∴点D坐标为(√3,2)，∴CD=CE−DE=2过点B作BF⊥l于点F，∴BF=OE=√3，∵BF+AE=OE+AE=OA=3√3，∴S△ABC=S△BCD+S△ACD=12CD⋅BF+12CD⋅AE，∴S△ABC=12CD(BF+AE)=12×2×3√3=3√3.【解析】本题考查的是待定系数法求二次函数的解析式、待定系数法求一次函数的解析式，用割补法求三角形面积，二次函数的图象和性质，解答时注意数形结合．(1)利用待定系数法求抛物线解析式；(2)利用割补法求ABC的面积．23.【答案】(1)证明：∵AF=FG，∴∠FAG=∠FGA，∵AG平分∠CAB，∴∠CAG=∠FAG，∴∠CAG=∠FGA，∴AC||FG，∵DE⊥AC，∴FG⊥DE，∵FG⊥BC，∴AC⊥BC，∴∠C=∠DHG=90∘，∠CGE=∠GED，∵F是AD的中点，FG||AE，∴H是ED的中点，∴FG是线段ED的垂直平分线，在△ECG和△GHD中，{GE=GD∠CGE=∠GDE ∠GDE=∠GED，∴△ECG≌△GHD(AAS)，∴GE=GD；(2)解：过点G作GP⊥AB于P，∴∠ACB=∠APG，在△CAG和△PAG中，{∠ACB=∠APG ∠CAG=∠GAB AG=AG，∴△CAG≌△PAG(AAS)，∴CG=PG，由(1)可得EG=DG，在Rt△ECG和Rt△DPG中，{CG=PGEG=DG，∴Rt△ECG≌Rt△DPG(HL)，∴EC=PD，∴AD=AP+PD=AC+EC；(3)解：∵D为FB中点，∴DG=DF，∴DG=DF=EF=EG，∴四边形AEGF是菱形．【解析】(1)利用{GE=GD∠CGE=∠GDE∠GDE=∠GED，证明△ECG≌△GHD(AAS)，即可求解；(2)通过证明△CAG≌△PAG(AAS)，Rt△ECG≌Rt△DPG(HL)，可得AD=AP+PD=AC+EC；(3)通过证明DG=DF=EF=EG，可得四边形AEGF是菱形．本题考查四边形的综合应用，熟练掌握三角形全等的判定及性质，菱形的性质，平行线的性质是。

( ) 45. --What are you up to?合肥市五十中东校2018-2019 学年度九年级第一学期第二次月考英语试题卷Ⅴ. 单项选择( ) 31. everyone has arrived, let’s start our class meeting.A. AlthoughB. BeforeC. So thatD. Now that( ) 32. --Did they the final game?--Sorry, I have no idea.A. beatB. defeatC. winD. look( ) 33. --Which team will the Chinese football team play ?--The Korean team.A. forB. onC. againstD. at( ) 34. Mr. Green an important meeting last Monday.A. joinsB. joinedC. taken part inD. took part in( ) 35. Bill runs fast no one can catch up with him in our class.A. too; toB. so; thatC. such; thatD. enough; to( ) 36. Please your homework before you hand it in.A. look; forB. look; afterC. look; outD. look; through( ) 37. As teenagers, we should study hard surfing the Internet all day.A. rather thanB. instead ofC. not justD. more than( ) 38. You will realize what I have done for you .A. any dayB. everydayC. one dayD. a day( ) 39. My cousin told me that he could eat three big apples .A. at timeB. at a timeC. some timeD. some times( ) 40. Now things made by machine are cheaper than those made .A. at handB. in handC. by handD. with hand( ) 41. Tony's trousers are his twin brother's. They have the same colour and size.A. different fromB. the sameC. similar toD. the same to( ) 42. Mr. Wang didn’t imagine a teacher in his childhood.A. becomingB. of becomingC. becomeD. to become( ) 43. --Have you seen the photos I took on my trip?--Yes, I have. They are fantastic.A. thatB. whoC. whatD. whom( ) 44. --I want to win the writing competition.-- .A. Oh, very funnyB. I bet you doC. Nice workD. It’s amazing-- .A. I was at homeB. I am fineC. I’m thirteenD. I’m looking for my penⅥ. 完形填空ATwelve students danced with twelve big schoolbags on Children’s Day. They wanted to show people how 46 they were! They looked forward to 47 small schoolbags. In fact, big schoolbags have been a serious problem for students for a long time. They are too 48 to carry,and it’s also not convenient(方便的) 49 students want to take a book out to read. But now thisproblem seems to be solved(解决). An e-textbook was invented and it will help 50 poorchildren.It is said that e-textbooks will be 51 in middle schools in our country. An e-textbook is asmall52 for each student. It’s 53 lighter than an ordinary schoolbag. Although it is as small as a book, 54 it can hold all things for study. Would you like to have 55 ?( ) 46. A. happy B. poor C. interesting D. exited( ) 47. A. taking B. bringing C. having D. carrying( ) 48. A. small B. big C. heavy D. light( ) 49. A. when B. where C. why D. what( ) 50. A. this B. that C. these D. them( ) 51. A. produced B. practiced C. made D. used( ) 52. A. pen B. computer C. bag D. book( ) 53. A. less B. much C. more D. many( ) 54. A. / B. but C. and D. so( ) 55. A. it B. own C. one D. aBA wealthy man loved his son very much. As he wanted his son to lead a happy life, he decided to send him to see a wise old man for his advice on happiness.When the old man learnt about his 56 ,he handed the boy an empty bowl and said, “Go to the river miles away and 57 it with water. I will tell you about it 58 no water is spilt(洒）whenyou reach here.” Although the boy was very surprised at this, he had no choice but to 59 this task.The boy 60 on foot for the river and some time later came back with a bowl of water. The old man asked him, "Did you notice the beautiful flowers along the road and tine birds singing in the trees?”The boy could say nothing about them because he gave his 61 attention to the bowl in his hands.The old man smiled and said, “Br ing me 62 bowl of water, but this time enjoy theflowers andWhen he returned, the boy was able to 63 everything he had seen to the old man. But whenhe looked down at his bowl, he found 64 that most water was gone. He forgot all about his bowl while enjoying the beautiful things along the road.“Well, young man,” the old man said. “Enjoy the beauty of the world, but never forget the water in your bowl. This is the 65 of happiness.”( ) 56. A. research B. promise C. purpose D. experience( ) 57. A. wash B. fill C. compare D. connect( ) 58. A. if B. until C. unless D. while( ) 59. A. put out B. pick out C. point out D. carry out( ) 60. A. set off B. paid off C. got off D. kept off( ) 61. A. public B. weak C. quick D. full( ) 62. A. any B. every C. another D. the other( ) 63. A. change B. imagine C. examine D. describe( ) 64. A. lazily B. sadly C. luckily D. excitedly( ) 65. A. result B. cause C. secret D. ideaⅦ. 补全对话Li Yang: Good morning, MatthewMatthew: Good morning, Li Yang. 66.Li Yang: There's still smog today. We'll have to go to school with face masks((口罩).Matthew: 67. According to the news, PM2. 5 pollution is the main problem with air pollutionLi Yang: Yes, and air pollution has done harm to people's health.Matthew: So the Chinese government and Chinese people must take action to fight it.Li Yang: 68.Matthew: Since Pm2.5 is mainly caused by vehicles( 机动车)and factories, cars with large emission(排放)should not be allowed and factories should be closely watched.Li Yang: 69. I hope that more and more people will join us in making the blue skies return for good.Matthey: 70.A.I hope so, too.B. Can you give any advice?C. I don't think.D. What a pity.E.I agree. Ⅷ. 阅读理解AA miser sold everything he owned and bought some gold with the money he got. “This gold will never get old,”he thought, “and it cannot break, so I can always sell it when I need money. However, gold is easy to steal, so I will bury(埋葬) it.”That same night, he went into a field and buried the gold. From time to time he went to the field and would dig up the gold to make sure it was still there. Then he would bury it again. A man who was building a house nearby saw the miser burying the gold again.One night, the man went into the miser's field, dug up the bar of gold, and stole it. The mister went to the hole the next day. He could not find the gold. He was very unhappy. A friend saw him crying and asked what was the matter. When the miser told him, the friend said, “Put some stones in the hole and pretend they are gold. You didn't use the gold when you had it, so it doesn't matter that there will only be some stones in the hole.”( ) 71. Why did the miser sell everything he owned and buy gold?A. Because he did not like anything that he owned any more.B. Because he thought that gold was easy to stealC. Because he thought that he could always sell it for moneyD. Because he wanted to have something to bury in the field( ) 72. Why did the miser bury his gold?A. Because it was easy to stealB. Because it was easy to buryC. Because he did not want the man nearby to see it.D. Because he wanted to keep it in the field( ) 73. What happened to make the miser unhappy?A. The miser spent all his money and was now poorB. A man broke into the miser's house and stole his goldC. The miser forget where he buried his goldD. A man dug up the miser's gold and stole it( ) 74. Why did the miser's friend tell him to put stones in the hole?A. Because he could sell them when he needed money.B. Because he could remember where he put them.C. Because he could watch the man try to steal them.D. Because he could pretend they were gold.BBecause of a deep fear of flying, a British boy who was named Joe Thompson had to stay in the United Arab Emirates(阿联酋)for 18 months. It was a long time for him.Joe had flown to Abu Dhabi, capital of the United Arab Emirates, with his family without any problem. But later, he developed an illness there and became afraid of flying. He was unable to return to Britain with his family as planned.While the rest of his family returned to Britain, Joe was forced to stay in the country with his father. Joe had tried four times to board a plane home. But each time he broke down(感情失控)in tears, he was unable to make the 4,500-mile journey. In order to overcome his deep fear of flying, his father asked a doctor for help. Mr. Hemmings is a British doctor who lives in the United Arab Emirates. He is a kind and friendly man. He offered to help Joe for free. He used hypnotherapy(催眠疗法) to help Joe stay calm during the flight. Thanks to hypnotherapy, Joe was able to return home at last.After reaching London, Joe said, “I'm so happy to be home. I can't believe how scary it is here!I really have to thank Dr. Hemmings. He helps me to come back home. I feel so good to be at home.”( ) 75. What does the underlined word "overcome" in Paragraph 3 mean?A. Fit forB. Insist onC. Care aboutD. Fight against.( ) 76. How did Joe feel when he tried 4 times to fly home?A. He felt OK. He flew with his family without any problem.B. He felt terrible and cried.C. He felt calm during the whole flight.D. He felt so good to be on the plane.( ) 77. Mr. Hemmings .A. is an American doctorB. lives in LondonC. offered to help Joe for freeD. kept Joe awake during the flight( ) 78. Which of the following statements is NOT true according to the passage?A. Joe Thompson was trapped in the United Arab Emirates for 18 months.B. Abu Dhabi is the capital of the United Arab Emirates.C. Joe Thompson was forced to stay in the United Arab Emirates alone.D. London is 4,500 miles away from Abu Dhabi.CStrawberries look nice, but a light pressure can make them out of shape. Nowadays, there are many young people who are just like strawberries. They easily break down when they face difficulties. They don't know what to do when they are in trouble. They have a common name- strawberry kids(草莓族).Why are many students so easy to break down? Parents and schools are a main reason. Parents do almost everything for them in their daily life, while schools care more about their grades instead of developing their personality.Liu Yue, 13, is from Fujian. His mom hardly criticizes(批评) him and he always feels good about himself. When a teacher criticized him strictly, he felt surprised and sad. He began to doubt his ability.Students should do something to make them mentally strong. An expert said, "When you are in trouble, don't ask for help too quickly. You should try to deal with problems first by yourself. I also advise you to take an active part in sports and social activities. That can make you mentally strong.”Growing up is not just a happy process. Pains also go along with it. The most important thing is to face the pains bravely and learn from them.( ) 79. Some students are called "strawberry kids" because .A. they are weak and need to be protected like strawberriesB. they all like to eat some fruit, for example, strawberriesC. they are out of shape under the great pressureD. they easily break down in the face of difficulties( ) 80. The underlined word “d oubt" probably means “_ " in Chinese.A. 培养B. 鼓励C. 怀疑D. 忽略( ) 81. In the fourth paragraph, the expert asked students to .A. take part in sports and social activitiesB. look for a chance to talk with parentsC. make friends with all of their classmatesD. ask for help quickly when they are in trouble( ) 82. The writer advises students to .A. pay more attention to studyB. ask parents to solve the problemC. care more about their gradesD. face the pains bravelyDEverywhere you look, there’s talk about exercise—from the importance of gym class to the latest trendy workout(流行的健身方式)to follow on social media. And as you know, being active is veryimportant, because it's good for your physical health, as well as helps with your mental health by improving your mood and keeping your mind sharp. Here is what people said about it.Alan-My friend and I try to exercise together. We dance to our favourite song or even enjoy a plank(平板支撑运动) contest. I think feeling strong is a good thing.Bill—I know I should exercise more, but I have no interest in it. Grace-Yoga(瑜伽)is the BESTway to exercise. I feel like everyone should try it. I take a class at the gym with my best friends, and it's so fun!Kitty—My dad tells me to exercise outside for at least an hour each day in summer. I do as hesays, and I always feel better after that. I believe I will go on. 90. What could football players see when they play football?!(不超过15 个词) Mary—In my spare time, I like reading instead of exercising. Every time I walk into the gym, Ialways feel nervous.( ) 83. How many people like exercising in the passage above?A. One.B. Two.C. Three.D. Four. ( ) 84. In Grace's opinion, what kind of exercise should everyone take?A. Plank.B. Swimming.C. Running.D. Yoga. ( ) 85. How does Mary feel when she is at the gym?A. strong.B. worried.C. Surprised.D. interesting. ( ) 86. Which statement is TRUE according to the passage above?A. Exercise can only be good for our physical health.B. Alan feels weak after he exercises with his friends.C. Bill doesn't have any interest in exercise.D. Kitty exercises at least two hours each day in summer.( ) 87. Where is the passage probably from?A. A magazine.B. A storybook.C. A novel.D. A notice. Ⅸ. 单词填空91. No one can be r (代替)in our class.92. The price of e (电子的) products changed a lot last year.93. The i (说明) of the computer can help you94. He was a young man with many a (能力).95. Can you explain it p (适当地) in English?Ⅹ. 书面表达读一本好书。

绝密★启用前2018-2019学年度第一学期九年级期末质量检测物理试卷一、填空题（每空2分，共26分）1、为应对城市的“热岛效应”，人们在城市规划时，常通过修建人工湖、景观湖来调节气候。

需要利用水的________大的特点，室外露天场所无法使用空调，人们就用喷雾装置向空气中喷洒水雾来降温，主要是利用水微粒在空气中________(天物态变化名称)时能吸收大量热量。

2、2018年4月，省能源局初步确定今年安徽风电开发方案项目中申报规模为150万千瓦，这样的规模发电1h获得的能量,相当于完全燃烧________t 无烟煤释放的能量。

（不计热量损失，煤的热值kg J /100.37⨯=无烟煤ρ）。

3、四冲程汽油机工作的一个循环中，除做功冲程外，其余三个冲程都是靠飞轮_______完成的。

4、春节期间，小朋友们常玩的一种无需用火点燃的鞭炮，只要稍用力砸向地面，它就可以点燃鞭炮与地面发生碰撞时，通过________的方式，使它的内能增加。

5、如图所示电路，R 1=2Ω，R 3=4Ω，总电压U =22V ，U 2=10V ，则R 2=_____Ω。

6、图中电源电压为3V ，电压表示数为1.8V ，电流表示数为0.2A ，则此时L 2灯丝电阻为________Ω。

7、在如图甲所示电路中，当闭合开关后，两个电压表指针偏转均如图乙所示，则电阻R 1两端的电压为______V 。

甲乙8、小明想利用电能表和手表测量家里的电水壶的电功率。

观察自家的电能表如图所示，将电水壶单独接在家庭电路中，记录到转盘6分钟内转了450转，则电水壶消耗的电能是________kw ∙h ，电水壶的功率是________w 。

9.已知甲和乙两灯的额定电压均为6V,如图是甲、乙两灯的电流随其两端电压变化的曲线.现将两灯串联后接在电源两端,在保证电路安全情况下，使其中一个灯泡正常发光,,则电源电压最大为 V,两灯消耗电能的总功率为 W ．10.如图是小明爸爸买的某品牌手机充电宝铭牌上的部分参数，由此可知该移动电源可以储存 J 的电能。

合肥市50中西校九年级（上）第三次月考（时间120分钟；满分150分）一、选择题（本大题共10小题,每小题4分,满分40分）1.抛物线2221,3,2y x y x y x ==-=共有的性质是（）A .开口向上B .都有最大值C .对称轴都是x 轴D .顶点都是原点2.如图,在Rt ABC 中,490, 10, 5C AB cos B ∠=︒=∠=,则BC 的长为（）A .6B .8C .9D .153.要得到二次函数2y x =的图像,将2(1)2y x =--+的图像如何移动()A .向左移动1个单位,向上移动2个单位； B.向右移动1个单位,向上移动2个单位；C.向左移动1个单位,向下移动2个单位；D.向右移动1个单位,向下移动2个单位；4.如果点C 是线段AB 的黄金分割点,那么下列线段比的值不可能是黄金比的是()A .:AB BCB .:BC ACC .:BC ABD .:AC BC5.如图,点P 在ABC 的边AC 上,要判断ABP ACB ,添加一个条件,不正确的是（）A.ABP C∠=∠ B.APB ABC∠=∠ C.AP ABAB AC= D.AB ACBP CB=6.反比例函数21k y x --=图象上有三个点112233(,),(,),(,)x y x y x y ,其中1230x x x <<<,则123,,y y y 的大小关系是（）A.123y y y << B.231y y y << C.132y y y << D.321y y y <<7.如图,将O 沿弦AB 折叠,圆弧恰好经过圆心O ,点P 是优弧 上一点,则APB ∠的度数为()A .30︒B .45︒C .60︒D .75︒8.如图的正方形方格纸中,每个小方格边长为1,,,,A B C D 都在格点处,AB 与CD 相交于O ,则sin BOD ∠的值等于()A.B.C.D.第2题图第5题图第7题图第8题图9.已知关于x 的二次函数221y x x =--,当2a x a ≤≤+时函数有最大值2,则 的值为()A.1-或1B.1或3- C.1-或3D.3或3-数关系的图像是（）C 二、填空题（本大题共4小题,每小题5分,满分20分）11.若23b a =,则a b b+=.12.如图,点A 在反比例函数(0)ky k x=≠的第二象限内的图像上,点B 在x 轴的负半轴上,AB AO =,ABO 的面积为6,则反比例函数的解析式为.13.如图,圆内接四边形ABCD 的边AB 过圆心O ,过点C 的切线与AD 的延长线交于点E ,若点D 是弧AC 的中点,且sin 70ABC ∠=︒,则AEC ∠=.14.如图,在Rt ABC 中,90C ∠=︒,6AC =,8BC =,点F 在边AC 上,并且2CF =,点E 为边BC 上的动点,将CEF 沿直线EF 翻折,点C 落在点P 处,则点P 到边AB 距离的最小值是.第12题图第13题图第14题图三、解答题（共90分）15.（82145sin 30tan 60602︒-︒︒+︒.16.（8分）已知二次函数223y x bx c =-++与x 轴的交点为(1,0)-和(3,0),求函数解析式并通过配方法求出最大值.连接PD .推理与运用：求证：18.（8分）如图,在ABC 中,AD BC ⊥于点D ,BE AC ⊥于点E .（1）求证:CDE CAB .（2）若60C ∠=︒,求:CDE CAB S S ．19.（10分）某海域有A,B两个岛屿,B岛屿在A岛屿北偏西30︒方向上,距A岛120海里,有一艘船从A岛出发,沿东北方向行驶一段距离后,到达位于B岛屿南偏东75︒方向的C处,求出该船与B岛之间的距离CB的长(结果保留根号).如图：21.（12分）如图,AB 是O 的直径,点C 在AB 的延长线上,CD 与O 相切于点D ,CE AD ⊥,交AD 的延长线于点E .．（1）求证：BDC A ∠=∠；（2）若4CE =,2DE =,求AD 的长．22.（12分）某工厂设计生产了一款汽车饰品,每件成本为30元,经过试销和市场调查得知,销售单价为50元时,每天的销售量为60件,而销售单价每降低1元,每天就可多售出4件,每涨价1元,每天就会少售出4件.(1)求每天的销售利润y(元)与销售单价x(元)之间的函数表达式；(2)求出销售单价为多少元时,每天的销售利润最大？最大利润是多少？(单价为整数)(3)如果该工厂要使每天的销售利润不低于1000元,且每天的总成本不超过2400元,那么销售单价应控制在什么范围内？(每天的总成本=每件的成本x 每天的销售量)23.（14分）我们知道,三角形三个内角平分线的交点叫做三角形的内心,已知点I为∆ABC的内心.(1))如图1,连接AI并延长交BC于点D,若AB=AC=3,BC=2,求ID的长;(2)如图2,过点I作直线交AB于点M,交AC于点N.①若MN⊥AI,求证: 证2= ∙ ;②如图3,AI交BC于点D,若∠BAC=60°,AI=4,求1 +1 的值合肥市50中西校九年级（上）第三次月考参考答案一、选择题12345678910C AD B CB A1.【解析】本题主要考查二次函数的图象与性质.A 项,抛物线221,2y x y x ==中0a >,所以开口向上,抛物线23y x =-中0a <,所以开口向下.故A 项错误.B 项,抛物线 = 2, =12 2开口向上,故有最低点.,最小值,抛物线 =−3 2的开口向下,故有最高点,最大值,故B 项错误.C 项中,抛物线2221,3,2y x y x y x ==-=的对称轴均为直线02b x a=-=,故抛物线2221,3,2y x y x y x ==-=共有的性质是对称轴是y 轴.故C 项错误.D 项,三个抛物线的顶点都是原点,故D 项正确.故选D .2.【解析】余弦值等于邻边比斜边,得出8BC =,故选B .3.【解析】左右平移,改变x ,左加右减；上下平移,改变y ,而且上加下减.故选C .4.【解析】由点C 是线段AB 的黄金分割点,2()AC AB BC AC BC =⋅>,则C 5-1AC 2AC B AB ==；或2B A ()C AB C AC BC =⋅<,则C 5-1AB 2AC B BC ==.故只有AB BC 的值不可能是5-12.故选A .5.【解析】在ACB 和ABP 中,AC CB AB BP =可变形为CBAB BPAC =,即两边对应成比例,但缺少夹角相等条件,不可证ABP ACB .故D 项符合题意,选D .6.【解析】210k --<,此函数的图象在二、四象限,在每一象限内y 随x 的增大而增大1230x x x <<<,所以10y >,230y y <<,所以231y y y <<,故选择B .7.【解析】根据折叠的性质得OD CD =,则12OD OA=根据含30度的直角三角形三边的关系得到30OAD ∠=︒120AOB ∴∠=︒60APB ∴∠=︒；故选C .8.【解析】将AB 向上平移一格,构造直角三角形,即可计算正弦值,故选B9.【解析】（1)21a +≤,即1a ≤-2max 212y a a =--=,1a =-,3a =(舍去)（2）1a ≥时,2max (2)2(2)12y a a =+-+-=,1a =,3a =-(舍去)（3）12a a <<+,即11a -<<时,max 02x x a y y y ==+==(舍去)综上1a =或1-故选A10.【解析】当m 从开始运动到与AC 重合时,2y x =;当直线m 从AC 运动到点B 时,28(4)y x =--故选C 二、填空题11.5212.6y x=-13.75︒146511.【解析】23b a =,则23b a =∴原式=253223a aa+=.12.【解析】作AC x ⊥轴,垂足为C .设(,)kA x x ,则CD x =-,2BD x =-,面积11A (2)622kS OB C x x=⋅=-⋅=,6k ∴=-.13.【解析】连接CO ,70ABC ∠=︒ 35DAC ∴∠=︒,70ACE ∠=︒180703575AEC ∴∠=︒-︒-︒=︒14.【解析】延长FP 交AB 于点D ,当FD AB ⊥时,点P 到AB 距离最小,此时PD FD PF =-,2FP FC ==,4AF AC FC =-=,在Rt ABC 中,2210AB AC BC =+=,所以84sin 105BC DF CAB AB AF ∠====,故45DF =⨯416455AF =⨯=,则点P 到边AB 的距离最小值为166255DF PF -=-=.三、解答题15.【解析】答案为34.16.【解析】根据交点坐标,代入得：43b =,2c =.19.【解析】作AD BC ⊥于点D ,如图所示30EAB ∠=︒ ,AE BF ,30FBA ∴∠=︒.又75FBC ∠=︒ ,45ABC ∴∠=︒120AB = AD BD ∴==Rt ADC 中,180********C ∠=︒-︒-︒-︒=︒tan 60ADCD ∴==︒BC BD CD ∴=+=海里20.【解析】（1）将(1,2)A -代入k y x =得2k =-,将(2,)B b 代入2y x=-得1b =-,所以B 的坐标为(2,1)B -.将A ,B 代入y mx n =+得221m n m n -+=⎧⎨+=-⎩,解得11m n =-⎧⎨=⎩(2)将0x =代入直线1y x =-+得1y =所以(0,1)C ,(0,1)D -所以2CD =112122322ABD ACD BCD S S S ∴=+=⨯⨯+⨯= .(3)对于1y x =-+,当0y =时,1x =,当点P 在x 轴上时,设点P 的坐标为(,0)a ,111211322PAB S a a =⨯-⨯+⨯-⨯= 解得：1a =-或3；当点P 在轴上时,设点P 的坐标为(0,)b ,111211322PAB S b b =⨯-⨯+⨯-⨯= 解得：1b =-或3,当1b =-时,P 与D 重合.所以P 点坐标为(1,0)-或(3,0)或(0,3).21.【解析】（1）连接OD ,如图所示.因为DC 与O 相切于点D ,所以OD CD ⊥,所以90ODC ∠=︒,90ODB BDC ∠+∠=︒因为AB 是O 的直径,所以90ADB ∠=︒所以90ADO ODB ∠+∠=︒,所以BDC ADO ∠=∠因为OA OD =,所以ADO A ∠=∠,所以BDC A ∠=∠（2） 因为CE AD ⊥,所以90E ∠=︒因为90ADB ∠=︒,所以BD CE ,所以BDC ECD ∠=∠,所以ECD EAC ∠=∠因为E E ∠=∠,所以ECD EAC ,所以DE CE CE AE =,所以22482CE AE DE ===所以826AD AE DE =-=-=22.【解析】（1）销售数量用m 来表示,根据题意得,销售数量m 和销售单价x 成一次函数关系设一次函数关系式为m kx b =+50604964k b k b +=⎧⎨+=⎩解得2604b k =⎧⎨=-⎩∴销售数量m 和销售单价x 的函数关系为4260m x =-+∴(30)(472060)(30)y m x x =-=-+-每天的销售利润y 与销售单价的函数表达式为243807800y x x =-+-(2)2295438078004()12252y x x x =-+-=--+40a =-< 抛物线的开口向下,对称轴是952x =,因为单价为整数，所以47x =或48时11所以y 的最大值是1224（3）当y =1000时,2954()122510002x --+=解这个方程,得140x=,255x =当4055x ≤≤时,每天的销售利润不低于1000元由每天的总成本不超过2400元,得30(4260)2400x -+≤,解这个不等式得,45x ≥4555x ∴≤≤销售单价应控制在45元至55元之间.23.【解析】(1)证明:如图1,作IE AB ⊥与E ,设ID x =3AB AC == ,AI 平分BAC∠AD BC ∴⊥,1BD CD ==再Rt ABD 中,22223122AD AB BD =-=-=,EBI DBI ∠+∠ ,90BEI BDI ∠+∠=︒,BI BI =BEI BDI∴ ID IE x ∴==,1BD BE ==2AE =在Rt AEI 中,222AE EI AI += 2222(22)x x ∴+=-2x ∴=2ID ∴=(2)如图2中,连接CI I 是内心MAI NAI ∴∠=∠AI MN ∴⊥90AIM AIN ∴∠=∠=︒()AI AI AMI ANI ASA =∴ AMN ANM ∴∠=∠,BMI CNI ∴∠=∠,设BAI CAI α∠=∠=ACI BCI β∠=∠=90NIC αβ∴∠=︒--18022ABC αβ∠=︒-- 90MBI αβ∴∠=︒--BMI INC ∴ BMMINI NC∴=NI MI = 2MI BM CN∴=⋅(3)过点N 作NG AD 交MA 的延长线于G30ANG AGN ∴∠=∠=︒AN AG ∴=,3NG AN=NG AD AM AIMG NG ∴=43AM AM AN AN∴=+113AM AN ∴==。

合肥五十中学天鹅湖教育集团2018~2019学年度第一学期九年级期中模拟卷班级：姓名：得分：一．选择题A．(3，4) B．(﹣3，4) C．(3，﹣4) D．(2，4)2．已知2x＝3y(y≠0)，则下面结论成立的是(※)A．xy＝32B．3x＝2yC．xy＝23D．2x＝3y3．下列4×4 的正方形网格中，小正方形的边长均为1，三角形的顶点都在格点上，则与△ABC 相似的三角形所在的网格图形是(※)A．B．C．D．4．若将抛物线y＝5x2先向右平移2个单位，再向上平移1个单位，得到的新抛物线的表达式为(※)A．y＝5(x﹣2)2＋1 B．y＝5(x＋2)2＋1 C．y＝5(x﹣2)2﹣1 D．y＝5(x＋2)2﹣1 5．如图所示，点P是□ABCD的对角线AC上的一点，过点P分别作PE∥BC，PF∥CD，交AB，AD于点E，F，则下列式子中不成立的是※)A．AFAD＝PEBCB．DFAF＝BEPFC．ADDF＝ABPFD．PFCDPEBC6．下表是一组二次函数y＝x2＋3x－5 的自变量x与函数值y的对应值：那么方程x2＋3x﹣5＝0 的一个近似根是(※)A．1 B ．1.1 C ．1.2 D．1.37．反比例函数y＝kx(k≠0)与二次函数y＝x2＋kx－k的大致图象是(※)A．B．C．D．8．美是一种感觉，当人体的下半身长与身高的比值越接近0.618时越给人一种美感．已知某女士身高160cm，下半身长与身高的比值是0.60，为尽可能达到好的效果，她应穿的高跟鞋的高度约为(※)A．6cm B．10cm C．4cm D．8cm9．如图，P是菱形ABCD的对角线AC上一动点，过P垂直于AC 的直线交菱形ABCD的边于M、N两点，设AC＝2，BD＝1，AP＝x，则△AMN的面积为y，则y关于x的函数图象的大致形状是(※)A ．B ．C ．D ．10．如图，△ABC 的三个顶点分别为A (1，2)，B (4，2)，C (4，4)．若反比例函数y =kx 在第一象限内的图象与△ABC 有交点，则k 的取值范围是(※) A ．1≤k ≤4 B ．2≤k ≤8 C ．2≤k ≤16 D ．8≤k ≤16二．填空题11．抛物线y ＝x 2＋bx ＋c 过点(﹣3，0)，(1，0)，则该抛物线的对称轴为 ．12．若ab ＝cd ＝2,则a c b d --＝13．飞机着陆后滑行的距离s (单位：米)与滑行的时间t (单位：秒)之间的函数关系式为s ＝60t ﹣1.5t 2．飞机着陆后滑行秒才能停下来．14．如图1，将正方形纸片ABCD 对折，使AB 与CD 重合，折痕为EF ．如图2，展开后再折叠一次，使点C 与点E 重合，折痕为GH ，点B 的对应点为点M ，EM 交AB 于N ．若AD ＝2，则MN ＝．三．解答题15．已知抛物线y ＝12x 2＋x －52．(1)用配方法求它的顶点坐标和对称轴；(2)若该抛物线与x 轴的两个交点为A ，B ，求线段AB 的长．16. 古代阿拉伯数学家泰比特•伊本•奎拉对勾股定理进行了推广研究：如图(图1中∠BAC 为锐角，图2 中∠BAC 为直角，图3 中∠BAC 为钝角)．在△ABC 的边 BC 上取 B '，C '两点，使∠AB 'B ＝∠AC 'C ＝∠BAC ，则 △ABC ∽△B 'BA ∽△C 'AC ，()'AB B B AB =，()'AC C C AC=进而可得AB 2＋AC 2＝ ； (用BB '，CC '，BC 表示) 若AB ＝4，AC ＝3，BC ＝6，则B 'C '＝ ．17．已知二次函数y＝ax2＋bx＋c的图象经过A(2，0)，B(0，－1)，C(4，5)三点．求二次函数的表达式．18．如图，在△ABC 中，AB=AC，D 在BC 上，且DE∥AC，交AB 于点E，点F 在AC 上，且DF＝DC．求证：△EBD∽△DFC.19．如图，直线y＝x＋1 与抛物线y＝x2－2mx＋m2＋m 交于A、B 两点（A 在B 左边）．求证：无论m 为何值，AB 的长总为定值．20．如图，在△ABC 中，D、E 在边BC 上，且△ADE是等边三角形，∠BAC＝120°．求证：DE2＝BD·CE21．已知：如图，反比例函数y＝kx的图象与一次函数 y＝x＋b 的图象交于点A(1，4)，B(－4，n)．(1)求一次函数和反比例函数的表达式；(2)求△OAB的面积；(3)直接写出一次函数值大于反比例函数值的自变量x的取值范围．22．根据对相关的市场物价调研，某批发市场内甲种水果的销售利润y 1(千元)与进货量x (吨) 近似满足函数关系y 1＝0.25x ，乙种水果的销售利润y 2(千元)与进货量x (吨)之间的函数y 2＝ax 2＋bx ＋c 的图象如图所示． (1)求出y 2与x 之间的函数关系式；(2)如果该市场准备进甲、乙两种水果共8 吨，设乙水果的进货 量为t 吨，写出这两种水果所获得的销售利润之和W (千元) 与t (吨)之间的函数关系式，并求出这两种水果各进多少吨时 获得的销售利润之和最大，最大利润是多少？23．如图，△ABC 中，∠ACB ＝90°，CD ⊥AB 于D ，点E 在AC 上，BE 交CD 于G ，EF ⊥ BE 交AB 于F ，CE ：BC ：AE ＝1：2：3.(1)求证：△BCE ∽△ACB ； (2)求证：BG ＝EG ；(3)求的值EFEB ．参考答案与试题解析一．选择题（共10小题）1．抛物线y＝2（x﹣3）2+4顶点坐标是（）A．（3，4）B．（﹣3，4）C．（3，﹣4）D．（2，4）故选：A．2．已知2x＝3y（y≠0），则下面结论成立的是（）A．＝B．＝C．＝D．＝故选：A．3．下列4×4的正方形网格中，小正方形的边长均为1，三角形的顶点都在格点上，则与△ABC相似的三角形所在的网格图形是（）A．B．C．D．故选：B．4．若将抛物线y＝5x2先向右平移2个单位，再向上平移1个单位，得到的新抛物线的表达式为（）A．y＝5（x﹣2）2+1 B．y＝5（x+2）2+1C．y＝5（x﹣2）2﹣1 D．y＝5（x+2）2﹣1故选：A．5．如图所示，点P是▱ABCD的对角线AC上的一点，过点P分别作PE∥BC，PF∥CD，交AB，AD于点E，F，则下列式子中不成立的是（）A．＝B．＝C．＝D．＝故选：C．6．下表是一组二次函数y＝x2+3x﹣5的自变量x与函数值y的对应值：A．1 B．1.1 C．1.2 D．1.3故选：C．7．反比例函数y＝（k≠0）与二次函数y＝x2+kx﹣k的大致图象是（）A．B．C．D．故选：B．8．美是一种感觉，当人体的下半身长与身高的比值越接近0.618时越给人一种美感．已知某女士身高160cm，下半身长与身高的比值是0.60，为尽可能达到好的效果，她应穿的高跟鞋的高度约为（）A．6cm B．10cm C．4cm D．8cm故选：D．9．如图所示，P是菱形ABCD的对角线AC上一动点，过P垂直于AC的直线交菱形ABCD的边于M、N两点，设AC＝2，BD＝1，AP＝x，则△AMN的面积为y，则y关于x的函数图象的大致形状是（）A．B．C．D．故选：C．10．如图，△ABC的三个顶点分别为A（1，2），B（4，2），C（4，4）．若反比例函数y＝在第一象限内的图象与△ABC有交点，则k的取值范围是（）A．1≤k≤4 B．2≤k≤8 C．2≤k≤16 D．8≤k≤16故选：C．二．填空题（共4小题）11．抛物线y＝x2+bx+c过点（﹣3，0），（1，0），则该抛物线的对称轴为x＝﹣1 ．12．若＝＝2，则＝ 2 ．13．飞机着陆后滑行的距离s（单位：米）与滑行的时间t（单位：秒）之间的函数关系式是s＝60t﹣1.5t2．飞机着陆后滑行20 秒才能停下来．14．如图1，将正方形纸片ABCD对折，使AB与CD重合，折痕为EF．如图2，展开后再折叠一次，使点C 与点E重合，折痕为GH，点B的对应点为点M，EM交AB于N．若AD＝2，则MN＝．三．解答题（共9小题）15．已知抛物线y＝x2+x﹣．（1）用配方法求出它的顶点坐标和对称轴；（2）若抛物线与x轴的两个交点为A、B，求线段AB的长．【解答】解：（1）∵y＝x2+x﹣＝（x+1）2﹣3，∴抛物线的顶点坐标为（﹣1，﹣3），对称轴是直线x＝﹣1；（2）当y＝0时，x2+x﹣＝0，解得：x1＝﹣1+，x2＝﹣1﹣，AB＝|x1﹣x2|＝．16．古代阿拉伯数学家泰比特•伊本•奎拉对勾股定理进行了推广研究：如图（图1中∠BAC为锐角，图2中∠BAC为直角，图3中∠BAC为钝角）．在△ABC的边BC上取B'，C'两点，使∠AB'B＝∠AC'C＝∠BAC，则△ABC∽△B'BA∽△C'AC，＝，＝，进而可得AB2+AC2＝BC（BB′+C′C）；（用BB'，CC'，BC表示）若AB＝4，AC＝3，BC＝6，则B'C'＝．【解答】解：∵△ABC∽△B'BA∽△C'AC∴＝，＝，∴AB2＝BC•B′B，AC2＝BC•C′C，∴AB2+AC2＝BC•B′B+BC•C′C＝BC（BB′+C′C）；∵AB＝4，AC＝3，BC＝6，∴42+32＝6（BB′+C′C），即6（BC﹣B′C′）＝25，∴6﹣B′C′＝，∴B′C′＝．故答案为BC（BB'+CC'）；．17．已知二次函数y＝ax2+bx+c的图象经过A（2，0），B（0，﹣1），C（4，5）三点．求二次函数的表达式．【解答】解：根据题意得：，解得：，∴二次函数的解析式为．18．已知：如图，在△ABC中，AB＝AC，D在BC上，且DE∥AC交AB于E，点F在AC上，且DF＝DC．求证：△EBD∽△DFC．【解答】证明：∵DE∥AC，∴∠EDB＝∠C．∵AB＝AC，∴∠B＝∠CFD．∴△EBD∽△DFC．19．如图，直线y＝x+1与抛物线y＝x2﹣2mx+m2+m交于A、B两点（A在B左边）．求证：无论m为何值，AB的长总为定值．【解答】解：∵直线y＝x+1与抛物线y＝x2﹣2mx+m2+m交于A、B两点，∴，解得或∴AB＝＝．∴无论m为何值，AB的长总为定值．20．如图，△ABC中，点D、E在边BC上，且△ADE是等边三角形，∠BAC＝120°，求证：DE2＝BD•CE．【解答】证明：∵△ABC是等边三角形，∴AD＝AE＝DE，∠ADE＝∠AED＝60°，∴∠ADB＝∠AEC＝120°，∵∠BAC＝120°，∴∠B+∠BAD＝∠BAD+∠CAE＝60°，∴∠B＝∠CAE，∴△ABD∽△CAE，∴，∴AD•AE＝CE•BD，∴DE2＝BD•CE．21．如图，反比例函数y＝的图象与一次函数y＝x+b的图象交于点A（1，4）、点B（﹣4，n）．（1）求一次函数和反比例函数的解析式；（2）求△OAB的面积；（3）直接写出一次函数值大于反比例函数值的自变量x的取值范围．【解答】解：（1）把A点（1，4）分别代入反比例函数y＝，一次函数y＝x+b，得k＝1×4，1+b＝4，解得k＝4，b＝3，所以反比例函数的解析式是y＝，一次函数解析式是y＝x+3；（2）如图，设直线y＝x+3与y轴的交点为C，当x＝﹣4时，y＝﹣1，∴B（﹣4，﹣1），当x＝0时，y＝3，∴C（0，3），∴S△AOB＝S△AOC+S△BOC＝×3×1+×3×4＝；（3）∵B（﹣4，﹣1），A（1，4），∴根据图象可知：当x＞1或﹣4＜x＜0时，一次函数值大于反比例函数值．22．根据对宁波市相关的市场物价调研，某批发市场内甲种水果的销售利润y1（千元）与进货量x（吨）近似满足函数关系y1＝0.25x，乙种水果的销售利润y2（千元）与进货量x（吨）之间的函数y2＝ax2+bx+c 的图象如图所示．（1）求出y2与x之间的函数关系式；（2）如果该市场准备进甲、乙两种水果共8吨，设乙水果的进货量为t吨，写出这两种水果所获得的销售利润之和W（千元）与t（吨）之间的函数关系式，并求出这两种水果各进多少吨时获得的销售利润之和最大，最大利润是多少？【解答】解：（1）∵函数y2＝ax2+bx+c的图象经过（0，0），（1，2），（4，5），∴，解得，∴y2＝﹣x2+x．（2）w＝（8﹣t）﹣t2+t＝﹣（t﹣4）2+6，∴t＝4时，w的值最大，最大值为6，∴两种水果各进4吨时获得的销售利润之和最大，最大利润是6千元．23．如图，△ABC中，∠ACB＝90°，CD⊥AB于D，点E在AC上，BE交CD于G，EF⊥BE交AB于F，CE：BC：AE＝1：2：3．（1）求证：△BCE∽△ACB；（2）求证：BG＝EG；（3）求的值．【解答】证明：（1）∵CE：BC：AE＝1：2：3，设EC＝a，BC＝2a，AE＝3a则AC＝4a，∴＝＝2，∵∠BCE＝∠ACB，∴△BCE∽△ACB，（2）∵△BCE∽△ACB，CD⊥AB，∴∠ABC＝∠BEC，∠BDC＝90°∵∠ABC+∠BCD＝90°，∵∠ACD+∠BCD＝90°，∴∠GEC＝∠GCE，∴GE＝GC，同理可证GB＝GC，∴BG＝EG．（3）∵∠A＝∠BCD，∴tan∠CBD＝tan∠A＝＝，设BD＝m，则CD＝2m．设BG＝CG＝x，在Rt△BDG中，∵BG2＝BD2+DG2，∴x2＝a2+（2a﹣x）2，∴x＝a，∴tan∠DBG＝＝＝，∴＝tan∠EBF＝．。

绝密★启用前合肥五十中新校（南校）九年级上期中测试卷（化学卷）满分100分第I 卷（选择题）一、本大题包括10小题，每小题2分，共20分；每小题的4个选项中只有1个选项符合题意。

1、下列安徽传统手工艺品的制作过程中，涉及化学变化的是（ ）A. B. C. D. 阜阳剪纸 徽州石刻 舒席编织 界首彩陶2、党的十八大报告提出建设“美丽中国”，我省各部门积极采取措施.下列做法正确的是（ ） A. 力推火力发电 B. 焚烧塑料垃圾 C. 推广使用公共自行车 D. 工业废水就近排放3、下列实验现象的描述中正确的是（ ）A. 汞在空气中加热时，产生了红棕色的氧化汞B. 铁丝在空气中剧烈燃烧，火星四射C. 硫粉在氧气中燃烧时，产生淡蓝色火焰，生成有刺激性气味的无色气体D. 水通电一段时间后，正极与负极产生的气体体积比约为1:24、下列实验操作正确的是（）.A. 量取9.3mL 液体B.点燃酒精灯C.倾倒液体D.收集氢气5、地壳中含有丰富的氧、硅、铝、铁元素，其有关信息如图所示，下列说法正确的是（ ）A. 氧原子核内质子数为6B. 硅元素位于元素周期表中第三周期C. 铝离子核外有三个电子层D. 铁原子的质量为55.85g6、最近科学家发现，水在-157℃超低温、正常压力或真空条件下仍呈液态，比蜂蜜还粘稠.下列关于这种“高密度液态水”的说法正确的是（ ）A. 化学性质与普通水不同B. 分子不再运动C. 氢、氧两种原子的个数比为2：1D. 分子间的间隔比普通水大7、用“”和“”表示不同元素的原子，下列微观示意图能表示化合物的是（ ）A. B.C.D.8、伟大壮观的国家大剧院主体建筑表面安装了近2万块钛（Ti ）金属板.已知Ti 原子核内有22个质子，则下列叙述正确的是（ ）A. Ti 可以表示一个钛原子B. Ti 4+核外有26个电子C. TiO 2中含有氧分子D. Ti 原子核内有22个中子9、1860年，英国科学家法拉第曾为少年儿童做过一个有趣的“母子火焰”实验，如图所示。

安徽省合肥市第五十中学西校区 2018-2019学年九年级第一学期第三次月考英语试卷（Word版，无听力无答案）Ⅵ.单项选择五十中学西校2018-2019 年度九年级英语第三次月考( ) 45. --Betty, I win the first prize in the photo competition!--Really? !A. CongratulationsB. You’re welcome( ) 31. Don’t throw away the paper. You can use on sides.A. it; everyB. them; allC. it; bothD. them; either( ) 32. --The model plane is wonderful! How did you make it?--It’s easy. Read the and you can do it too.A. discussionB. instructionsC. introductionD. information( ) 33. Mr. Black’s son died from an accident. He is very sad and , because his son isC. Sorry to hear thatD. You’re in with a chanceⅦ. 完形填空AIn Australia, different people have different ways to enjoy themselves. They also have their own ideas about 46 to pass time.the only of his life. 47 children, about 80%, work hard in school because they have to take lots of exams. AfterA. hope; hopefulB. hopeful; hopeC. hopeless; hopeD. hope; hopeless( ) 34. He managed to complete this difficult task he was in very poor health.A. in order thatB. because ofC. as a resultD. even though( ) 35. My grandmother enjoys newspapers after dinner every day, and she often tells me something new in the world.A. looking upB. looking forC. looking atD. looking through( ) 36. Touri sts’ bad behavior by the government in our country from now on.A. will recordB. will be recordedC. recordsD. is recorded( ) 37. I will never forget the people and the place I visited last year.A. whoB. whichC. whereD. that( ) 38. You are not supposed to go to Alice’s party if you .A. won’t i nviteB. won’t be invitedC. are not invitedD. were not invited( ) 39. --Tom, don’t be . You should tidy your bedroom every day.--Sorry, Mum. I will do it now.A. lazyB. busyC. carelessD. shy( ) 40. It’s no use me about him, because I don’t know anything.A. to askB. askingC. askD. asks( ) 41. --Have you found the information about the famous people you can use for the report?--Not yet. I’ll s earch some on the Internet.A. whoB. whereC. whomD. which( ) 42. --This summer holiday, we’ll notices to call on people to protect our environment.A. put upB. put onC. put offD. put down( ) 43. --Will you go to plant trees in the mountains?-- ! I do so every Tree-Planting Day.A. You’re jokingB. No wayC. You betD. Nice work( ) 44. -- the school rules, students mustn’t go out of the school after nine o’c lock at night.A. According toB. Thanks toC. Compared withD. Instead of school, they don’t want to stay at home reading books any more. 48 , they put aside their school bags and go out to play.Some old people 49 early in the morning. Then they go to park to 50 . It helps them know what is happening around the world. In the evening, they would prefer to stay at home 51 rather than do anything else.Young people enjoy having 52 trip on weekends. They go to mountains to have a picnic or go to the 53 to camp. They usually start on Friday and spend one or two days outside. Then on 54 evening, they start their way back home. 55 seems to be in a hurry, although a busy week is waiting for them again.( ) 46. A. what B. how C. when D. why( ) 47. A. Some B. Most C. All D. No( ) 48. A. However B. Though C. Instead D. Or( ) 49. A. get up B. come up C. stay up D. set up( ) 50. A. read newspapers B. do sports C. enjoy themselves D. have breakfast ( ) 51. A. climbing hills B. watching TV C. go shopping D. going hiking( ) 52. A. boring B. busy C. tiring D. relaxing( ) 53. A. forest B. floor C. flat D. factory( ) 54. A. Friday B. Sunday C. Tuesday D. Wednesday( ) 55. A. Anybody B. Somebody C. Everybody D. NobodyBHave you eaten at a restaurant where the robots serve you? I think most people haven’t done it. There is a restaurant like that in Chongqing. A robot has started 56 customers at a high-tech highway restaurant.When you come into the entrance(入口),the robot will greet you in a(n) 57 voice and then she will take you to your table. The robot names Amy. She is 58 with people especially children. Amy can find the right way 59 to avoid walking into customers or other restaurant’s human. When 60 sit beside the table ,they can order the food on the table. The table is 61 a big screen. And then the robot can serve their food on time. Customers can also 62 the bill with amobile phone App on their phones, such as Alipay(支付宝) or WeChat Pay. Orders are placed at two tables as touch screens. 63 they wait for their order, customers can use the special tables Ⅸ. 阅读理解Ato play games, read the news, and check the traffic and weather 64 for their journey ahead. This 65 restaurant is part of Chongqing’s “s mart highway rest shop” plan. Do you want to have a try at this restaurant?( ) 56. A. missing B. marking C. serving D. leading( ) 57. A. sweet B. loud C. noisy D. ugly( ) 58. A. difficult B. patient C. lucky D. popular( ) 59. A. hardly B. easily C. really D. widely( ) 60. A. customers B. workers C. waiters D. managers( ) 61. A. about B. like C. for D. against( ) 62. A. spend B. cost C. take D. pay( ) 63. A. When B. Because C. If D. So( ) 64. A. marks B. messages C. conditions D. blackboards( ) 65. A. lovely B. cheap C. beautiful D. specialⅧ.补全对话A: Hi, Alice. 66.B: Yeah, I’d like to do some traveling.A: 67.B: Not yet.A: Do you want to travel in big cities?B: 68.A: How about Mountain Huang?B: 69.A: Sure! In China, itˈs considered to be the king of all the mountainsB: 70.A: Right. You can see special pines, rocks and clouds. You can enjoy hot springs as well.B: Great! Thank you.A. Glad to help you.B. What else can we enjoy?C. Is it worth(值得) traveling there?D. Have you decided where to go?E. Then it must have something special.F. I don’t think it fun to travel in big cities.G. Do you have any plan for the summer holiday?Disney Park in Florida is close to the beach. Here’s some advice for visiting Disney Park in Florida:★ You can purchase tickets online or at a Disney store.★ Free parking (停车). You can drive there if you like.★ Get to the park early, or it will be crowded.★ Free drinking water! You just need to take your water bottle.★ If you love Disney characters, visit before you go there. Then you can easily find where all the characters appear in the park.★ Lunch is usually served (供饭菜) until 3:45 pm. The money you need to pay depends on which character you would like to eat with.★ You can get into the park for free on your birthday.( ) 71. The underlined wo rd “purchase” mean s “_”.A. showB. checkC. buyD. sell( ) 72. The sixth piece of advice is about .A. playingB. eatingC. sleepingD. parking( ) 73. People can visit before going to the park so that they can easily find .A. drinking waterB. lunch tablesC. parking placesD. Disney characters( ) 74. What can we know from the passage?A. The park is on the right of the beach.B. People can go to the park by bus.C. People can have dinner after 3:45 pm.D. You can get into the park without paying on your birthday.BWhen Juliet was a child, she often went to the city park and played with her friends. On a sunny morning, when Juliet came to the park with her mum, she looked around and felt very unhappy. "What's the matter, dear?" asked her mum.Juliet replied, "Mum, there's so much trash on the ground."Juliet's mum looked around. There was paper, boxes and glass bottles everywhere."What can we do?" asked Juliet."I'm sure you will think of something," said her mum.As soon as Juliet and her mum went home, Juliet painted a picture of the park and wrote a sign in large black letters at the top of the picture. The sign read "PLEASE KEEP OUR PARK CLEAN". Later, she took plenty of bags and went back to the park with her mum. Juliet put up her picture on a big trash can (垃圾桶)."Will you help me pick up the trash, Mum?" Juliet said as she handed her mum a bag."I sure will," replied her mum.Many students like to work with computers, which makes learning more fun." said Tingting, a The children at the park ran over to see what was going on. Juliet handed them each a bag."Let's clean this place up," said Juliet. Then they began to pick up the trash, talking and laughing.Soon all the bags were full."We need to come back another day. There's still some trash on the ground, but the park looksmuch better," said Juliet.Her mum said, "So it does. I knew you would think of a way to help."( ) 75. Why was Juliet sad?A. Because the weather was bad.B. Because she couldn’t find her mum.C. Because her friends were not at the park.D. Because there was too much trash at the park.( ) 76. Juliet put up the picture to .A. show off her painting skillsB. give her mum a big surpriseC. encourage people to keep the park cleanD. show people how beautiful the park was( ) 77. From the passage, we can learn that Juliet's mum .A. was proud of JulietB. was angry with JulietC. thought Juliet was lazyD. thought Juliet was difficult( ) 78. What did the children at the park do?A. They laughed at Juliet.B. They put up a notice.C. They bought some bags from Juliet.D. They joined Juliet in picking up the trash.( ) 79. What's the topic(主题) of the passage?A. A clean up story.B. Juliet and her mum.C. A beautiful park.D. How to protect the environment.CMr. Guo is a teacher from Xi'an. He asked his students to hand in their homework through a QRcode(二维码). "We spent an hour or two in class learning how to generate (使产生) the codes, andin the end everything gets easier," said Guo. "When students finish the homework, they keep it onWeChat (微信). Then, each student makes his own QR code and gives it to me. So I can checktheir work everywhere using my computer or telephone."The QR codes can be sent to Mr. Guo by email, QQ and WeChat. When Guo scans (扫描) hisstudents' QR codes, their homework appears on his phone. He finds that their homework becomesmore creative (创新的), with many pictures, music and even videos.Guo's students like the new way and think it is interesting. "We are living in the information age.After that, Mr. Clinton said, "This is the most wonderful thing that ever happened to us. My boy student of Guo's."The paper is not easy to keep, but the code is easy to keep and share." Guo said. "It is worthtrying to use new technology in education. Education itself is a kind of creation. I don't want mystudents to fall behind the times."However, some parents are worried. They are afraid that their children will spend too much timeon computers and less time communicating with teachers. But in fact, it's unnecessary. Studentsstill need to look up information in books and write it down when they do their homework. Theyonly use the code when they hand in their work, which doesn't take them too much time. Also forteachers, it allows them to check the students' work at any time. And it's also an easy way to sharehomework with other students.( ) 80. According to the passage, students can keep their homework on .A. WeChatB. QQC. emailD. blog (博客)( ) 81. Guo's students think the new way is .A. strangeB. boringC. interestingD. unnecessary( ) 82. What does "it" in Paragraph 4 refer to (指代)?A. The paper is not easy to keep.B. Keeping and sharing the code easily.C. Trying to use new technology in education.D. Education itself is a kind of creation.( ) 83. Some parents are worried, because they think their children will .A. talk with teachers face to faceB. spend too much time on computers or phonesC. not like the new way of handing in homeworkD. find the QR codes too difficult to useDMr. Clinton and his 13-year-old son Tony are basketball fans. Last October 10th was Tony'sbirthday, so Mr. Clinton decided to drive him to New York, for the first game of the World Series.They had no ticket but hoped to buy a pair from scalpers.After they arrived, they walked in the street for two hours, carrying a sign that read, "We needtwo tickets." There were many scalpers around, but the cheapest ticket was $200. They wereabout to leave when suddenly a man stopped them. He took out two tickets and handed them toMr. Clinton. "How much do you want?" "Just a present," said the man. "Enjoy the game."Mr. Clinton wouldn't accept, so the man explained, "I'm Jackson. Hans is my boss. He and hiswife haven't missed a World Series for 18 years. But he is ill and can't watch the game this time.So he told me to give the two tickets to people who I thought would actually enjoy the game. Andyou made me think of my dad and me when I was a child. I dreamed of going to a World Seriesgame with my father. But my dream never came true."and I still never forget Jackson and the Hans."( ) 84. What did Mr. Clinton do to celebrate his son's 13th birthday?A. To watch a movie together.B. To watch a football match together.C. To watch a basketball match together.D. To go shopping to New York together.( ) 85. Why couldn't Hans and his wife watch the game that time?A. Because they were too busy.B. Because Mr. Hans was ill and his wife had to look after him.C. Because they weren't interested in it.D. Because they wanted to get more money.( ) 86. What does the underlined word "scalpers" in the first paragraph mean?A. 售票员B. 检票员C. 票贩子D. 小商贩( ) 87. What can we know according to the passage?A. Mr. Clinton got two tickets which were given as a present.B. Mr. Clinton and his son Tony spent almost two hours to get to the game place.C. Mr. Jackson went there to look for his friend Mr. Clinton and his son.D. Mr. Jackson's dream came true at last.E任务型阅读Once I worked in a new company and I found something really strange. One of my colleagues(同Ⅹ. 单词拼写根据首字母及汉语提示,完成下列单词的拼写91. She s (受……折磨) from a great pain in her left leg, but she didn’t stop training.92. Keeping a d (日记) is a good habit of improving your writing skill.93. In the 18th century, this type of pop music (蔓延)all over the countryside.94. The government sets a high s (标准) for the safety of food.95. They were brave enough to fight e (敌人).Ⅺ.书面表达为响应我市全面创建国家卫生城市的号召，某校开展了以“绿色滨湖，健康生活”为主题的英语征文活动。

合肥市五十中学西校教育集团九年级入学教育检测英语一、单项选择（每小题1分，1.I find ________ necessary to learn about the customs of a country before you go there．A.thatB.thisC.itD.one2. ---Where is Mr. Wang?---He together with his students ________ Cunjin Park．A.have gone toB.has been toC.has gone toD.have been to3. Lucy has some secrets. She wants to have a ________ talk with us.A.richB.cuteC.privateD. public4. I’m sleepy. I prefer ________ at home to going out.A.sleepingB.to sleepC.sleptD.sleep5. We have decided to go to Chao Hu for a trip, but we couldn’t ________ when to go.A.count downB.keep upC.agree one out6. Bob is taking the desks away because they ________ too much room.A.stand upB.pick upC.take upD.listen up7. When we are reading in the library, we should avoid ________ any noise.A.makeB.madeC.to makeD.making8. —Excuse me. Could you tell me ________ ?—In about half an hour, I think. You can wait and have a cup of tea.A. how soon would John be backB.how long will John be backC. how long John would be backD. how soon John will be back9. We should study hard _______ we can get much knowledge.A.whenB.so thatC.unlessD.in order to10._______ it was only four o’clock the lights were already on.A.AlthoughB.SinceC.IfD.Until11.—Your bedroom is so clean.—Of course. It _______ every day.A.cleansB.cleanedC.is cleanedD.was cleaned12.I hate the dogs _______ live in the next house. They make loud noises all night.A.whoB.thatC.whatD.whom13.My brother _______ for the bus when the rainstorm came.A. has waitedB. was waitingC. waitsD. is waiting14.—Will you keep these old toys?—Of course. They hold the sweetest _______ about my childhood.A. goldB. silenceC. researchD. memory15.They were all very tired,but _______ of them stopped a rest.A.all;haveB.both;to haveC.none;to haveD.no one;having16.This term Jim has made great _______ in English. His teacher is pleased with him.A.progressB.exerciseC.mistakesD.excuses17.Have you _______ the apples? Can you tell me the _______？A.weighed ; weighedB.weight ; weightC.weighed ; weightD.weight ; weighed18.I could _______ speak any English when I first came to England.A.evenB.hardlyC.finallyD.ever19.The weather reporter says the nice weather will _______ for another week.stB.askC.waitD.search20.—Thank you for the ride!—_____________.A.Sounds greatB.My pleasureC.With pleasureD.Good luck二、完形填空（每小题1分，共10 分）Winter becomes colder and colder. People begin to wear more 1 themselves against the cold. But 2 do animals get through the long cold winter?A number of animals, especially birds, travel to 3 places to get away from the cold. Wild geese, for ex ample, fly south. Other animals, such as bears, snakes and squirrels, 4 most of their time eating or stor ing food. After enough food and energy preparation, they go to safe places to hibernate (冬眠). Hibernation is a special and deep sleep. When animals hibernate, their body temperature drops,and their heartbeat and breathing become very 5. They look like dead ones. The largest hibernators are bears. 6 other hibernators, bears do not eat or drink while hibernating, which can lastas 7 as six months.For some cold-blooded animals, 8 gives them a good place to keep warm. 9 the weathergets c old, they move to the bottom of lakes or ponds. For insects(昆虫), most of them don’t10 during the winter, which is called diapause (昆虫生长的停滞期).( )1. A. protect B. protecting C. protects D. to protect( )2. A. how B. what C. where D. why( )3. A. cooler B. warmer C. colder D. windier( )4. A. cost B. spend C. take D. pay( )5. A. quick B. strong C. slow D. noisy( )6. A. Instead B. Except C. Unlike D. Without( )7. A. long B. much C. many D. far( )8. A. land B. water C. air D. space( )9. A. Since B. When C. For D. Even( )10. A. sleep B. talk C. grow D. stop三、补全对话（每小题1分，共5分）A: Hi, Wang Fang. I haven’t seen you for days.21.___F___B: I have been to Beijing.A: 22.___B___B: I took part in the First Chinese Ancient Poem Reading Competition.A: Really? How did you perform?B: 23.___C___A: Congratulations! You are always the best. Whose poem did you choose?B: I chose Li Bai’s. He is my favorite poet.A: I like his poems, too. 24.___D___B: Fantastic! We should learn more about our Chinese ancient poems.A: 25. ___G___ It’s our duty to keep and spread our traditional culture.B: That’s right.A. Have you ever been to Beijing?B. What did you do there?C. I won the first place.D. And what do think of the competition?E. I went on Wednesday.F. Where have you been?G. I agree with you.四、阅读理解（每小题2分，共20分）AA boy and his father were walking in the mountains. Suddenly the boy fell, hurt himself, and cried, “AAAh hhhhhhh!!!” To his surprise, he heard the voice repeating(重复), somewhere in the mountains, “AAAhhhhhhhh!!!” Then the boy shouted, “Who are you?” He received the answer, “Who are you?” He got angry at the answer, so he shouted, “Foolish!” He received the answer, “Foolish!”He looked at his father and asked, “What’s going on? ” The father smiled and said, “My son, l isten.” And t hen he shouted to the mountain, “I love you!” The voice answered, “I love you!” Again the man cried, “Yo u are the best!” The voice answered,“You are the best!”The boy was surprised, but did not understand. Then the father explained, “People call this ‘Echo’, but reall y this is Life. It gives you back everything you say and do. Our life is just a reflection(反映) of what we have done. If you want more love in the world, please have more love in your heart. If you want to be successful, work hard. Life will give you back everything you have given to it. This is a useful l esson in life. ”51. Why did the boy cry at first ?A. He wanted to give himself a surprise.B. He felt down and hurt himself.B. He felt it was so quiet in the mountains.D. He hoped his father would help him.52. When the boy heard the voice repeating, he thought ______ .A. it was foolish to hear others’ voice.B. someone else in the mountains liked his voice.C. there were many other people in the mountains.D. he was laughed at by someone else in the mountains.53. Why did the father shout to the mountain？A. To find out who was repeating his voice.B. To have fun with other people in the mountains.C. To let his son know whose voice was louder.D. To show more examples to his son before giving him the answer.54. What does the underlined word “Echo” mean?A. 回声.B. 讽刺.C. 淘气.D. 反映.55. What can we know from the story?A. The boy didn’t like others’ voice at all.B. It is not polite to repeat others’ voice.C. The father had his own way to teach his son.D. The boy and his father were rather tiredBDifferent from popular thoughts, colds are not caused by bad weather. Colds are caused by viruses(病菌) in the body, and you are better on the snowy day than you are in a warm room, with your friends, who j ust may be passing the virus around. If you feel a chill(颤抖) when you are coming down with a cold, you are already sick. A chill is an early sign of the cold.The virus can spread through air when a cold-sufferer(感冒患者) coughs or sneezes. Surprisingly this is not the most usual way of spreading, Many studies have now sh own that most colds are “caught” by hands. A cold-sufferer rubs her nose, so spreading the virus to her han d. Then a friend comes to visit her. They shake their hands. The friend then gets something to eat by hand, and several days later she catches a cold. Although some parents pick up their children’s tissues(纸巾) and carefully throw them away，they fail to wash their hands. They’ll catch the colds, too.Cold viruses can also be spread by objects, for example, telephones, plates. The cold-sufferer as well as oth er members of the house by washing their hands often, will stop the viruses from spreading in a way.56. What are colds caused by according to the popular thoughts?A. Bad weatherB. ChillC. VirusesD. Your friends57. In what situation may people have caught a cold according to the passage?A. When they pick up their children’s tissues.B. When they stay in a warm room.C. When they want to shake hands with friends.D. When they feel a chill with a cold.58. Which of the following sentences is true in the passage？A. An early sign of the cold is viruses in the body.B. The virus can’t spread through air.C. Objects can carry cold viruses, too.D. Few colds are “caught” by hands.59. How do people catch colds more often?A. By rubbing their noses.B. By shaking their hands.C. By coughing and sneezing.D. By washing their hands.60. What does the passage mainly tells us?A. Washing hands is a way to keep us from catching colds.B. Colds are caused by bad weather.C. The cold-sufferer shakes hands with her friends.D. We should stay in a warm room on the snowy day.五、任务型阅读（每小题2分，共10分）Have you ever seen the film Traveling Bird? In the film, groups of birds fly high above the sky and cross the way above snow, rivers, fields, sea and grassland. I'm sure you will love the beautiful picture when you see the film.But you may not feel so good if you have learnt about bird flu(禽流感) from TV or on the Internet. Some governments had to kill chickens in their cities. A large number of chickens and even some people died in Asia, and nearly 8, 500 birds died in Russia because of bird flu.Chickens can get bird flu from the feces(粪便) of the passing birds. It is not so difficult to control the chickens in cages or on farms. But it is much more difficult to control the birds in the sky.Luckily, scientists have found a medicine for bird flu. But the virus(病毒) can change easily and quickly. So bird flu is still a serious problem we must face.46.How do people learn about bird flu? (不超过6个词）________________________________________________________________47.How many birds died in Russia because of bird flu?________________________________________________________________48.Is it more difficult to control the birds in the sky or the chickens in cages?________________________________________________________________49.Have scientists found a medicine for bird flu?________________________________________________________________50.Why is bird flu still a serious problem?________________________________________________________________六、用单词的适当形式填空（每小题2分，共10分）51.It was quite ________ (silence) and there was no sign of it.52.There were lots of ________ in ancient China.53.The gardener found only a few leaves r__________ (剩下) on the tree.54.Please collect the ___________ (最新的) news about football matches.55.She has just celebrated her ________ (twenty) birthday. 56.Real friendship is more _______ (value) than money.57.Before we begin dinner, we l_______ the table.58.The teacher is very h__________ (幽默的), and she tells funny stories.59.In her o_______, it’s easy to work it out.60.To save _________(电), we should turn off the lights when we go out.七、句型转换（每小题2分，共10分）61. I have already started.(变成否定句)I _______ started _______.62.It rained heavily. As a result, he was late.(同义句转换)He was late ________ ________ ________ ________ the heavy rain.63.The little boy was too weak to lift the box up.(同义句转换)The little boy was not ________ ________ to lift the box up.64.The nurse looked after the patients well.(同义句转换)The nurse ________ ________ ________ ________ the patients.65.Will you take a boat tour with us? They asked me.(合并成一句)They asked me ________ ________ take a boat tour with them or not.66.We provide some books for you.(同义句转换)We ________ you ________ some books.67.I got off the car and walked along a dark path.I ________ ________ ________ the car and walked along a dark path.68.69.The reporter was nervous when he interviewed the president for the first time.(同义句转换)The reporter was nervous when he ________ ________ ________ with the president for the first time.70.71.He seemed to be more interested in natural wonders.(同义句转换)________ ________ ________ he was more interested in natural wonders.72.73.It is time for breakfast.(同义句转换)It is time ________ ________ breakfast.八、书面表达（满分15分）假如你是张华，收到了笔友Tina的邮件，Tina说她最近不开心。

合肥市50中东区2018-2019学年度九年级（上）期中考试（时间120min ；满分150分）一、选择题（每题4分，共40分）1. 1. 下列二次函数的图象，不能通过函数下列二次函数的图象，不能通过函数的图象平移得到的是（的图象平移得到的是（ ）） A. B. C. D.2.2.下列各组线段中，不能成比例的是（下列各组线段中，不能成比例的是（ ））A. B.C.D .3.3.若抛物线若抛物线与轴的交点为,则下列说法不正确的是（则下列说法不正确的是（ ））A. 抛物线的开口向上B.抛物线的对称轴是C. 当时，的最大值为D . . 当当时,随增大而增大 4.4.反比例函数反比例函数的图像经过点,若，则的取值范围为（的取值范围为（）） A. B. C.或 D.或 5.5.如图，如图，中，为上一点，在下列四个条件中：①，②,③,④,能使和相似的条件是（ ）A. ①②③B.①③④①③④C. ①②④D.②③④ 第5题图题图 第6题图y =3x 22y =3x 2+2 y =3(x -1)2 y =3(x -1)2+2y =2x 2 a =3,b =6,c =2,d =4a =1,b =2,c =6,d =3 a =4,b =6,c =5,d =10a =2,b =5,c =15,d =6 y =x 2-2x +c y(0,-3) x =1 x =1 y -4 x ³2y xy =kxA (2,1) y £1 xx ³1 x ³2 x <0 0<x £1 x <0 x ³2 D ABC P AB ÐACP =ÐB ÐAPC =ÐACB AC 2=AP ·AB AB ·CP =AP ·CB D APC D ACB6.6.如图，反比例函数如图，反比例函数的图像经过矩形的边的中点，则矩形的面积为（ ） A.2 B. 4 C.5 D.87.7.在平面直角坐标系中，已知点在平面直角坐标系中，已知点,以原点为位似中心，相似比为,把缩小，则点的对应点 A /的坐标是的坐标是( ) ( )A. B. C.或 D.或8.8.已知抛物线已知抛物线上有三点，则的大小关系为（ ）A.y 1>y 2>y 3B. C . D.9.a ¹0,函数与在同一平面直角坐标系中的大致图象可能是（ ））A. B. C. D.10.10.如图所示，已知点如图所示，已知点分别是中、边的中点，相交于点，S EFG =1，则四边形的面积是（的面积是（）） A.7 B.8C.9D.10第第10题图题图 第14题图 二、填空题（每题5分，共20分）y =2xOABC AB D OABCA (-4,2),B (-6,-4) O 1/2 D ABO A(-2,1)(-8,4) (-8,4)(8,-4) (-2,1)(2,-1)y =-12(x -1)2+kA (-2,y 1),B (-1,y 2),C (2,y 3)y 1,y 2,y 3 y 3>y 2>y 1 y 2>y 3>y 1y 2>y 1>y 3y =a xy =-ax2+aE ,F D ABC AC ABBE ,CF G BCEF11.11.反比例函数反比例函数的图象在第一、三象限，则的取值范围是的取值范围是 . . 12.12.河北省赵县的赵州桥的拱桥是近似的抛物线形，建立如图所示的平面直角坐标系，其函数的关系式为河北省赵县的赵州桥的拱桥是近似的抛物线形，建立如图所示的平面直角坐标系，其函数的关系式为,当水面离桥拱顶的高度为时，这时水面宽度为.第第12题图题图 第13题图13.13.如图，平面内有如图，平面内有16个格点，每个格点小正方形的边长为2，则图中阴影部分的面积，则图中阴影部分的面积 . .14.14.如图，点如图，点坐标为，点是线段上的一个动点（不运动至两点）过点作轴，垂足为，以为边在右侧作正方形，连接并延长交轴的正半轴于点，连接，若以为顶点的三角形与 D OEF 相似，，则的坐标是的坐标是 . .三、（本大题共2小题，每小题8分，满分16分）15. 15. 已知函数已知函数23-2-1y x x =，求出此抛物线与坐标轴的交点坐标y =m -1xmy =-125x 2 DO4mABA(1,1) C OAO ,A C CD ^x D CD CDEF AF x B OFB ,E ,F B16.16.装卸工人往一辆大型运货车上装载货物，装卸工人往一辆大型运货车上装载货物，装卸工人往一辆大型运货车上装载货物，装完货物所需时间装完货物所需时间()min y 与装载速度()/min x t 之间的函数关系如图：（1）求y 与x 之间的函数关系式；（2）货车到达目的地后开始卸货，如果以1.5/m in t 的速度卸货，需要多长时间才能卸完货物？四、（本大题共2小题，每小题8分，满分16分）17.17.如图所示，如图所示，小明从路灯下向前走了5米，发现自己在地面上的影子长DE是2米，如果小明的身高是1.6米，求路灯离地面的高度AB18. 18. 如图，已知反比例函数如图，已知反比例函数6y x =的图象与一次函数y kx b =+的图象交于点()1,A m ，(),2B n 两点（1）求一次函数的解析式）求一次函数的解析式; ;（2）直接写出不等式6kx b x³+的解集；五、（本大题共2小题，每小题10分，满分20分）19. 如图,内在同一平面内,,将两个全等的等腰直角三角形A B C 和A F G 起摆放在一起,,A 点为公共顶点,,90BAC AGF Ð=Ð= .AF AG 、与边BC 的交点分别为D E 、 ( (点点D 不与点B 重合重合,,点E 不与点C 重合重合). ). (1)(1)图中共有对相似而不全等的三角形图中共有对相似而不全等的三角形图中共有对相似而不全等的三角形. . (2)(2)选取其中一对进行证明选取其中一对进行证明选取其中一对进行证明..20.20.如图，在直角坐标系中，抛物线经过点如图，在直角坐标系中，抛物线经过点()()()041,0,5,0A B C ，， （1）求抛物线的解析式和顶点E 坐标（2）该抛物线有一点D ，使得S D DBC =S D EBC ,求点D 的坐标.六、（本题满分12分）21.21.如图是如图是35´的网格，的网格，正方形网格中的每个小正方形边长都是正方形网格中的每个小正方形边长都是1，每个小格的顶点叫做格点，每个小格的顶点叫做格点，以格点为顶以格点为顶点的图形叫做格点图点的图形叫做格点图. .（1）图1中的格点ABC D 与DEF D 相似吗？请说明理由．（2）请在图2中选择适当的位似中心作111A B C D 与ABC D 位似，且相似比不为1（3）请在图3中画一个格点222A B C D 与ABC D 相似（注意：222A B C D 与ABC D 、DEF D 、111A B C D 都不全等）图图1 图2 图3七、（本题满分12分）22. 22. 俄罗斯世界杯足球赛期间，俄罗斯世界杯足球赛期间，某商店销售一批足球纪念册，每本进价40元，规定销售单价不低于44元，且获利不高于30%30%．．试销售期间发现，当销售单价定为44元时，每天可售出300本，销售单价每上涨1元，每天销售量减少10本，现商店决定提价销售．设每天销售量为y 本，销售单价为x 元．（1）请直接写出y 与x 之间的函数关系式和自变量x 的取值范围；（2）将足球纪念册销售单价定为多少元时，商店每天销售纪念册获得的利润w 元最大？最大利润是多少元？八、（本题满分14分）23. 23. 已知正方形已知正方形ABCD 的对角线 AC ,BD 相交于点 O .(1)(1)如图如图 1 ,,E G 分别是 ,OB OC 上的点上的点,,CE 与DG 的延长线相交于点F . . 若若D F C E ^,求证求证::O E O G = ；(2)(2)如图如图2 ，H 是BC 上的点，过点H 作E H B C ^，交线段OB 于点E ，连结DH 交CE 于点 F ，交OC 于点G . 若O E O G =，①求证①求证::O D G O C E Ð=Ð； ②当1AB =时，求HC 的长的长..合肥市50中东校2018-2019学年度九年级（上）期中考试参考答案一、选择题1．【解析】【解析】A A 选项，原图像向上平移2个单位；个单位；B B 选项，原图像向右平移1个单位；个单位；C C 选项，原图像向右平移1个单位，向上平移2个单位；个单位；D D 选项，不能得到。

2023-2024学年安徽省合肥五十中新校九年级（上）开学物理试卷一、填空题（本大题共10小题，每空2分，共26分）1. A，B两物体叠放在水平桌面上，如图所示，当右端挂5N的物体C时，物体A、B恰好能一起向右做匀速直线运动，若对物体B施加一个水平向左的力使物体A，B一起向左做匀速直线运动，绳与滑轮间的摩擦忽略不计，该力的大小为______ N。

2. 如图所示，上表面水平且光滑的小车上有A、B两个物体，两物体与小车以相同的速度一起向右匀速运动.B在A的正前方，B的质量小于A的质量.假设小车的上表面足够长，不计空气阻力，小车遇到障得物突然停止后，A、B两物体之间的距离______(选填“保持不变”“逐渐变长”或“逐渐变短”)。

3. 火星周围也笼罩着大气层，火星表面大气压强为600Pa左右。

“600Pa”表示的物理意义是______。

4. 睿佳购买了一包A4型号复印纸，从外包装纸上得知它共有500张、总的厚度为5cm，她还发现上面标有70g/m2字样，经查询后才知道指的是每平方米复印纸的质量是70g。

请利用以上信息计算：一张复印纸平摊在水平地面上对地面压强为______ Pa(g取10N/kg)。

5. 如图所示，运−20军用运输机静止时轮胎对跑道的压强为p1，在机场跑道高速滑行时轮胎对跑道的压强为p2，则p1______ p2(填“大于”、“小于”或“等于”)。

6. 如图甲所示，一个棱长为10cm、重为9N的正方体物块M，水平放置在一个方形容器中，M 与容器底部不密合。

以恒定水流向容器内注水，容器中水M的深度ℎ随时间t的变化关系如图乙所示，图乙中a的值为______ cm(g=10N/kg)。

7. 现有甲、乙两个实心物块，密度分别为水的3倍和5倍，分别将它们悬挂在弹簧测力计挂钩下并浸没在水中，发现弹簧测力计减少了相同的示数，则甲、乙两个物体所受浮力之比为______，此时挂甲、乙的两个弹簧测力计的示数之比为______。