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《生活中的轴对称》测试题1

《生活中的轴对称》测试题1
《生活中的轴对称》测试题1

《生活中的轴对称》单元测试题 1

一、填空题:

1.等腰三角形的两个内角之比是1:2,那么这个等腰三角形的顶角度数为___________.

2.ΔABC和ΔA’B’C’关于直线L对称,若ΔABC的周长为12cm,ΔA’B’C’的面积为6cm2,则ΔA’B’C’的周长为___________,ΔABC的面积为_________。

3.△ABC中,AD⊥BC于D,且BD=CD,若AB=3,则AC=_____.

4.等腰三角形的周长为22 cm,其中一边的长是8 cm,则其余两边长分别为_____.

5.轴对称图形_____有一条对称轴,_____有两条对称轴,_____

有四条对称轴,_____有无数条对称轴.(各填上一个图形即可)

6.如图,是用笔尖扎重叠的纸得到的成轴对称的两个图形,则AB 的对应线段是, EF的对应线段是∠C的对应角是连结CE交L于O,则⊥,且=

7.如图,OC平分∠AOB,D为OC上任一点,DE⊥OB于E,若DE=4 cm,则D到OA的距离为_____.

8.如图,在△ACD中,AD=BD=BC,若∠C=25°,则∠ADB =.

9.如图,裁剪师傅将一块长方形布料ABCD沿着AE折叠,使D点落在BC边上的F点处,若∠BAF=60°,则∠DAE= . 10.如图,在△ABC中,∠C=90°,DE是AB的垂直平分线,∠A=40°,则∠CDB= ,∠CBD= .

11.如图,在ΔABC中AB=AC,∠A=36°,BD平分∠ABC,则∠

1=_______, 图中有______个等腰三角形。

12.如图,ΔABC中AB=AC,AB的垂直平分线MN交AC于点D.

(1).若∠A=38°,则∠DBC=______________。

(2).若AC+BC=10cm,则ΔDBC的周长为___________。

13.如图,从镜子中看到一钟表的时针和分针,

此时的实际时刻是________。

14.等腰三角形的周长是25 cm,一腰上的中线将周长分为3∶2两部分,则此三角形的底边长为_____.

二.选择题。

1.如图所示,下列图案是我国几家银行的标志,其中不是轴对称图形的有

( )

2.两个图形关于某直线对称,对称点一定在( )

A.这直线的两旁B.这直线的同旁

C.这直线上D.这直线两旁或这直线上

N

B

3.下列说法中,不正确的是 ( ) A .等腰三角形底边上的中线就是它的顶角平分线

B .等腰三角形底边上的高就是底边的垂直平分线的一部分

C .一条线段可看作以它的垂直平分线为对称轴的轴对称图形

D .两个三角形能够重合,它们一定是轴对称的

4.在线段、直线、射线、角、等腰三角形、任意的一个三角形、五角星这些图形中,轴对称图形有( ) A .6个 B .5个 C .4个

D .3个

5.将一张矩形的纸对折,然后用笔尖在上面扎出“B ”,再把它铺

平,你可见到( )

6.

7. 如图是人字形屋架的设计图,由AB 、AC 、BC 、AD 四根钢条焊接而成,其中A 、B 、C 、D 均为焊接点,且AB=AC ,D 为BC 中点,现在焊接所需的四根钢条已截好,且已标出BC 的中点D ,如果焊接工身边只有可检验直角直尺,那么为了准确快速地焊接,他首先应焊接的两根钢条及焊接点是( )

A.AB 和BC ,焊接点B

B.AD 和BC ,焊接点D

C. AB 和AC ,焊接点A

D. AB 和AD ,焊接点A

8.下列图形中,不是轴对称图形的是 ( ) A .有两个内角相等的三角形 B. 有一个内角是45°直角三角形 C. 有一个内角是30°的直角三角形 D. 有两个角分别是30°和120°的三角形

9.下列说法中正确的是 ( ) ① 角平分线上任意一点到角的两边的线段长相等

② 角是轴对称图形 ③ 线段不是轴对称图形

④ ④ 线段垂直平分线上的点到这条线段两个端点的距离相等 A.①②③④ B.①②③ C. ②③④ D. ②④ 10.下列图形中,线段AB 和A ’B’ (AB=A ’B’)不 关于直线L

对称的是 ( )

L

L

B B'

A'

L

B

A'

B

A

D B

7题图

右下方折 右折 沿虚线剪开 A B

C D

A .

B.

C.

D.

11.小明从镜子里看到镜子对面电子钟的像如图所示实际时间是 ( )

A .21:10 B. 10:21 C. 10:51 D. 12:01

12.如图,直线1l ,2l ,3l 表示三条互相交叉的公路,现要建一个货

物中转站,要求它到三条公路的距离相等,则可供选择的地址有( ) A.1处 B.2处 C. 3处 D.4处 三.解答题。

1. 如图,已知:△ABC 中,BC <AC ,AB 边上的垂直平分线DE 交

AB 于D ,交AC 于E ,AC=9 cm,△BCE 的周长为15 cm,求BC 的长

. 3. 已知,如图ΔABC 中,AB =AC,D 点在BC 上,且BD =AD ,DC =

AC.将图中的等腰三角形全都写出来.并求∠B 的度数.

4. 以给定图形“○○、△△、 ”(两个圆、两个等边三角形、两条平行线段)为构件,构思独特且有意义的轴对称图形.举例:如图,左框中是符合要求的一个图形。你还能构思出其它的图形吗?请在右框中画出与之不同的一个图形,并写出一两句贴切、诙谐的

解说词.

解说词:两盏电灯 解说词 5. (5分)某汽车探险队要从A 城穿越沙漠去B 城,途中需要到河流L 边为汽车加水,汽车在河边哪一点加水,才能使行驶的总路程最短?请你在图上画出这一点.

7(6分).如图,已知P

点是∠AOB 平分线上一点,PC

⊥OA ,PD ⊥OB ,垂足为C 、D , (1)∠PCD=∠PDC 吗? 为什么?(2)OP 是CD 的垂直平分线吗? 为什么?

1l 3

l 2l

D

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