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15 20 10 绝密★启用前

济南市2010年初三年级学业水平考试

数 学 试 题

注意事项:

1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分,满分120分.第Ⅰ卷1

至2页,第Ⅱ卷3至8页.考试时间120分钟.

2.答第Ⅰ卷前,考生务必将自己的姓名、准考证号、考试科目用2B 铅笔涂写在答题

卡上,并同时将考点、姓名、准考证号、座号填写在试卷规定的地方.

3.选择题选出答案后,用2B 铅笔把答题卡上对应题目的正确答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其它答案,答案写在试卷上无效.

4.数学考试不允许使用计算器,考试结束后,应将本试卷和答题卡一并交回.

第Ⅰ卷(选择题 共48分)

一、选择题(本大题共12个小题,每小题4分,共48分.在每小题给出的四个选项中,只

有一项是符合题目要求的.) 1.2+(-2)的值是 A .-4

B .1

4

-

C .0

D .4

2.一组数据0、1、2、2、3、1、3、3的众数是 A .0 B .1 C .2 D .3

3.图中的几何体是由7个大小相同的小正方体组成的,该几何体的俯视图为

4.作为历史上第一个正式提出“低碳世博”理念的世博会,上海世博会从一开始就确定以“低碳、和谐、可持续发展的城市”为主题.如今在世博场馆和周边共运行着一千多辆新能源汽车,为目前世界上规模最大的新能源汽车示范运行,预计将减少温室气体排放约28400

吨.将28400吨用科学记数法表示为

A .0.284×105 吨

B .2.84×104吨

C .28.4×103吨

D .284×102吨 5.二元一次方程组42x y x y -=??+=?的解是

A .3

7

x y =??=-?

B .11

x y =??=?

C .73

x y =??=?

D .31

x y =??=-?

6.下列各选项的运算结果正确的是

A .236(2)8x x =

B .22523a b a b -=

C .623x x x ÷=

D .222()a b a b -=-

第4题图 A .

B .

C .

D . 第3题图

第10题图 A B

C

D

P

E

第12题图

A

B

C

D

M N

O 第9题图

1+8=? 1+8+16=?

⑵ ⑶

1+8+16+24=?

第11题图

…… 7.在一次体育课上,体育老师对九年级一班的40名同学进行了立定跳远项目的测试,测试所得分数及相应的人数如图所示,则这次测试的平均分为 A .5

3

分 B .354分 C .403分 D .8分

8.一次函数21y x =-+的图象经过哪几个象限

A .一、二、三象限

B .一、二、四象限

C .一、三、四象限

D .二、三、四象限

9.如图所示,正方形ABCD 中,对角线AC 、BD 交于点O ,点M 、N 分别为OB 、OC 的中点,则cos ∠OMN 的值为 A .1

2

B

C

D .1

10.二次函数22y x x =--的图象如图所示,则函数值y <0时

x 的取值范围是

A .x <-1

B .x >2

C .-1<x <2

D .x <-1或x >2

11.观察下列图形及图形所对应的算式,根据你发现的规律计算1+8+16+24+……+8n (n 是正

整数)的结果为

A .2(21)n +

B .2(21)n -

C .2(2)n +

D .2n 12.如图所示,矩形ABCD 中,AB =4,BC

=,点E

是折线段A -D -C 上的一个动点(点E 与点A 不重合),点P 是点A 关于BE 的对称点.在点E 运动的过程中,使△PCB 为等腰三角形的点E 的位置共有 A .2个 B .3个 C .4个 D .5个

A

C D E 第14题图

绝密★启用前

济南市2010年初三年级学业水平考试

数 学 试 题

注意事项:

1.第Ⅱ卷共6页.用蓝、黑色钢笔或圆珠笔直接答在考试卷上. 2.答卷前将密封线内的项目填写清楚.

第Ⅱ卷(非选择题 共72分)

二、填空题(本大题共5个小题,每小题3分,共15分.把答案填在题

中的横线上.)

13.分解因式:221x x ++= .

14.如图所示,△DEF 是△ABC 沿水平方向向右平移后的对应图形,若∠B =31°,∠C =79°,

则∠D 的度数是 度.

15.解方程

23

123

x x =

-+的结果是 . 16.如图所示,点A 是双曲线1

y x

=-

在第二象限的分支上的任意一点,点B 、C 、D 分别是点A 关于x 轴、原点、y 轴的对称点,则四边形ABCD 的面积是 .

17.如图所示,△ABC 的三个顶点的坐标分别为A (-1,3)、B (-2,-2)、C (4,-2),则

△ABC 外接圆半径的长度为 .

A

第19题图

三、解答题(本大题共7个小题,共57分.解答应写出文字说明、证明过程或演算步骤.)

18.(本小题满分7分)

⑴解不等式组:224x x x +>-??-?

⑵如图所示,在梯形ABCD 中,BC ∥AD ,AB =DC ,点M 是AD 的中点. 求证:BM =CM .

19.(本小题满分7分)

0(3)-

⑵如图所示,△ABC 中,∠C =90°,∠B =30°,AD 是△ABC 的角平分线,若AC 求线段AD 的长.

B A

C D

M 第18题图

20.(本小题满分8分)

如图所示,有一个可以自由转动的圆形转盘,被平均分成四个扇形,四个扇形内分别标有数字1、2、-3、-4.若将转盘转动两次,每一次停止转动后,指针指向的扇形内的数字分别记为a、b(若指针恰好指在分界线上,则该次不计,重新转动一次,直至指针落在扇形内).

请你用列表法或树状图求a与b的乘积等于2的概率.

21.

(本小题满分8分)

如图所示,某幼儿园有一道长为16米的墙,计划用32米长的围栏靠墙围成一个面积为120平方米的矩形草坪ABCD.求该矩形草坪BC边的长.

第20题图

第21题图

A B C N

M P

A M N P 1 P 2

B A

C M N

1 2 2009…… ……

B 第23题图2 第23题图1 第23题图3 第22题图

22.(本小题满分9分)

如图所示,菱形ABCD 的顶点A 、B 在x 轴上,点A 在点B 的左侧,点D 在y 轴的正半轴上,∠BAD =60°,点A 的坐标为

(-2,0).

⑴求线段AD 所在直线的函数表达式.

⑵动点P 从点A 出发,以每秒1个单位长度的速度,按照A →D →C →B →A 的顺序在菱形的边上匀速运动一周,设运动时间为t 秒.求t 为何值时,以点P 为圆心、以1为半径的圆与对角线AC 相切?

23.(本小题满分9分)

已知:△ABC 是任意三角形.

⑴如图1所示,点M 、P 、N 分别是边AB 、BC 、CA 的中点.求证:∠MPN =∠A . ⑵如图2所示,点M 、N 分别在边AB 、AC 上,且

13AM AB =,1

3AN AC =,点P 1、P 2是边BC 的三等分点,你认为∠MP 1N +∠MP 2N =∠A 是否正确?请说明你的理由.

⑶如图3所示,点M 、N 分别在边AB 、AC 上,且

12010AM AB =,1

2010

AN AC =

,点P 1、P 2、……、P 2009是边BC 的2010等分点,则∠MP 1N +∠MP 2N +……+∠MP 2009N =____________.

(请直接将该小问的答案写在横线上.)

24.(本小题满分9分)

如图所示,抛物线223y x x =-++与x 轴交于A 、B 两点,直线BD 的函数表达式为y =+l 与直线BD 交于点C 、与x 轴交于点E .

⑴求A 、B 、C 三个点的坐标.

⑵点P 为线段AB 上的一个动点(与点A 、点B 不重合),以点A 为圆心、以AP 为半径的圆弧与线段AC 交于点M ,以点B 为圆心、以BP 为半径的圆弧与线段BC 交于点N ,分别连接AN 、BM 、MN .

①求证:AN =BM .

②在点P 运动的过程中,四边形AMNB 的面积有最大值还是有最小值?并求出该最大值或最小值.

绝密★启用前

济南市2010年初三年级学业水平考试

数学试题参考答案及评分标准

一、选择题

13. 2(1)x + 14. 70 15. 9x =- 16. 4 17. 三、解答题

18.(1)解:224x x

x +-??-?

>≤

解不等式①,得1x ->, ·································································· 1分 解不等式②,得2x ≥-, ··································································· 2分 ∴不等式组的解集为1x ->. ···································································· 3分 (2) 证明:∵BC ∥AD ,AB =DC ,

∴∠BAM =∠CDM , ··································································· 1分 ∵点M 是AD 的中点,

∴AM =DM , ··············································································· 2分

∴△ABM ≌△DCM , ································································· 3分 ∴BM =CM . ················

································································ 4分 19.(1)解:原式

0(3)- ·

·························································· 1分 2+1 ··

·············································································· 2分 -1 ··················································································· 3分

(2)解:∵△ABC 中,∠C =90o,∠B =30o,

∴∠BAC =60o,

∵AD 是△ABC 的角平分线,

∴∠CAD =30o, ···································································

········

·· 1分 ∴在Rt △ADC 中,cos30AC

AD =

?

················································· 2分

················································ 3分

=2 . ························································ 4分

20.解:a 与

·················································································································· 6分 总共有16种结果,每种结果出现的可能性相同,其中ab =2的结果有2种, ··························································································································· 7分

第22题图 ∴a 与 b 的乘积等于2的概率是1

8

. ·························································· 8分

21.解:设BC 边的长为x 米,根据题意得 ··················································· 1分 321202

x x -= ,

················································································· 4分 解得:121220x x ==,, ··········································································· 6分

∵20>16,

∴220x =不合题意,舍去, ································································· 7分

答:该矩形草坪BC 边的长为12米. ··············································· 8分 22. 解:⑴∵点A 的坐标为(-2,0),∠BAD =60°,∠AOD =90°,

∴OD =OA ·tan60°

=,

∴点D 的坐标为(0

,), ···························································· 1分 设直线AD 的函数表达式为y kx b =+,

20

k b b -+=???

=??

,解得k b ?=??=?? ∴直线AD

的函数表达式为y +. ······································· 3分 ⑵∵四边形ABCD 是菱形, ∴∠DCB =∠BAD =60°, ∴∠1=∠2=∠3=∠4=30°, AD =DC =CB =BA =4, ········································································· 5分 如图所示:

①点P 在AD 上与AC 相切时, AP 1=2r =2, ∴t 1=2. ·································································································· 6分

②点P 在DC 上与AC 相切时,

CP 2=2r =2,

∴AD +DP 2=6, ∴t 2=6. ·······································7分

③点P 在BC 上与AC 相切时,

CP 3=2r =2,

∴AD +DC +CP 3=10,

∴t 3=10. ·······································8分

④点P 在AB 上与AC 相切时, AP 4=2r =2,

∴AD +DC +CB +BP 4=14, ∴t 4=14,

∴当t =2、6、10、14时,以点P 为圆心、以1为半径的圆与对角线AC 相切. ··························································· 9分

D

C M

N

O A B P 第24题图

l

x y

F

E A

B

C

M N

P 1 第23题图

P 2

1 2

23. ⑴证明:∵点M 、P 、N 分别是AB 、BC 、CA 的中点, ∴线段MP 、PN 是△ABC 的中位线,

∴MP ∥AN ,PN ∥AM , ··················· 1分

∴四边形AMPN 是平行四边形, ····· 2分 ∴∠MPN =∠A . ···························· 3分 ⑵∠MP 1N +∠MP 2N =∠A 正确. ··················· 4分 如图所示,连接MN , ···························· 5分

1

3

AM AN AB AC ==,∠A =∠A , ∴△AMN ∽△ABC , ∴∠AMN =∠B ,

1

3

MN BC =, ∴MN ∥BC ,MN =1

3

BC , ······················· 6分

∵点P 1、P 2是边BC 的三等分点,

∴MN 与BP 1平行且相等,MN 与P 1P 2平行且相等,MN 与P 2C 平行且相等, ∴四边形MBP 1N 、MP 1P 2N 、MP 2CN 都是平行四边形, ∴MB ∥NP 1,MP 1∥NP 2,MP 2∥AC , ······································································ 7分 ∴∠MP 1N =∠1,∠MP 2N =∠2,∠BMP 2=∠A , ∴∠MP 1N +∠MP 2N =∠1+∠2=∠BMP 2=∠A . ····································································· 8分 ⑶∠A . ···················································· 9分

24.解:⑴令2230x x -++=,

解得:121,3x x =-=, ∴A (-1,0),B (3,0) ······························· 2分 ∵223y x x =-++=2(1)4x --+, ∴抛物线的对称轴为直线x =1,

将x =1

代入y =+y

∴C (1,

. ··································· 3分 ⑵①在Rt △ACE 中,tan ∠CAE

=

CE

AE

=, ∴∠CAE =60o,

由抛物线的对称性可知l 是线段AB 的垂直平分线, ∴AC=BC ,

∴△ABC 为等边三角形, ·································································· 4分 ∴AB = BC =AC = 4,∠ABC=∠ACB = 60o,

又∵AM=AP ,BN=BP , ∴BN = CM ,

∴△ABN ≌△BCM , ∴AN =BM . ···························································································· 5分 ②四边形AMNB 的面积有最小值. ··················································· 6分 设AP=m ,四边形AMNB 的面积为S ,

由①可知AB = BC= 4,BN = CM=BP ,S △ABC ×42=, ∴CM=BN= BP=4-m ,CN=m , 过M 作MF ⊥BC ,垂足为F ,

则MF =MC ?sin60o)m -,

∴S △CMN =12CN MF =1

2

m )m -=2+, ·

························ 7分 ∴S =S △ABC -S △CMN

=-(2

22)m -+ ·

············································································ 8分

∴m =2时,S 取得最小值 ·························································· 9分

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