【三明数学答案】2023年三明市初三5月质检卷.pdfVIP

三明市2022－2023学年初中毕业班第二次教学质量检测

数学参考答案

说明：不同于本参考答案的解答，按相应步骤给分.

一、选择题：本题共10小题，每小题4分，共40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.D2.D3.A4.B5.C6.B7.B8.A9.C10.C

二、填空题：本题共6小题，每小题4分，共24分.

13

11.112.513.14.415.−16.①③④

35

三、解答题：本题共9小题，共86分.解答应写出文字说明、证明过程或演算步骤.

4−=3，

17.解：{①

2−5=−3.②

①-②×2得

9y=9

∴y=1····································································3分

把y=1代入①得

4x-1=3

∴x=1·······································································6分

∴方程组的解为{=1·················································8分

=1

E

18.证明：∵CE∥AB，

∴∠DCE=∠A.····················································3分

A

∵CD=AB,∠CDE=∠B，D

∴△CDE≌△ABC．·························································6分

∴DE=BC.··········································································8分BC

3−（+2）(−1)2

19.解：原式=÷…………………..2分

+2+2

3−−2+2

=∙…………………..4分

+2(−1)2

1−+2

=∙

+2(−1)2

1

=.…………………..6分

1−

31时

当a=

11√3

原式===−.…………………..8分

1−1−(√3+1)3

20.（1）如图所示，