章末作业
一、选择题
1．下列图形中∠1和∠2互为对顶角的是( ).
A． B．
C． D．
2．如图，点E在AC的延长线上，下列条件能判断AB∥CD的是( ).
A．∠D＝∠DCE
B．∠3＝∠4
C．∠1＝∠2
D．∠D＋∠ACD＝180°
3．下列语句中，不是命题的是( ).
A．两点之间线段最短
B．对顶角相等
C．过直线AB外一点P作直线AB的垂线
D．不是对顶角不相等
4．如图，AB∥CD，若∠1＝65°，∠2＝120°，则∠3的度数为( ).
A．45° B．55°
C．60° D．65°
5．光线在不同介质中的传播速度是不同的，因此光线从空气斜射入水中要发生折射．物理课上，小军手持一激光笔射入水中，如图，水面与水杯下沿平行，光线从空气射入水中，发生折射，若∠1＝60°，∠ABO＝140°，则∠2的度数是( ).
A．10° B．20°
C．30° D．40°
6．将一个含30°角的三角尺和直尺如图放置，若∠1＝50°，则∠2的度数是( ).
A．30° B．40°
C．50° D．60°
7．如图，已知a∥b，则∠ACD的度数是( ).
A．45° B．60°
C．70° D．73°
二、填空题
8．命题“如果实数a，b满足a＞b，那么|a|＞|b|”的题设是____________________，它是________(选填“真”或“假”)命题．
9．如图，直线l分别与直线a，b相交，a∥b，若∠1＝71°，则∠2的度数为________．
10．如图，AB∥CD，EC⊥CD于点C，CF交AB于点B，若∠2＝30°，则∠1＝________°.
11．如图，将一条对边互相平行的纸带进行两次折叠，折痕分别为AB和CD.若CD∥BE，∠1＝62°，则∠2的度数为________．
12．如图，将一副直角三角尺的其中两个顶点重合叠放(∠A＝30°，∠ABC＝60°，∠D＝∠BED＝45°).三角尺ABC固定不动，将三角尺DBE绕点B转动．当DE∥BC时，∠ABE的度数为________．
13．如图，3条直线两两相交最多有3个交点，4条直线两两相交最多有6个交点，按照这样的规律，则10条直线两两相交最多有________个交点．
三、解答题
14．如图，在正方形网格中，每个小正方形的顶点称为格点．利用不带刻度的直尺作图．
(1)找一个格点D，过点C画AB的平行线CD；
(2)过点A画BC的垂线，垂足为E；
(3)线段AE与AC的大小关系是______(用“＜”号连接)，依据是_____________________________________________________________．
15．如图，AB∥CD，CE⊥AD，垂足为E，若∠A＝38°，求∠C的度数．
16．如图，∠BAP＋∠APD＝180°，∠AOE＝∠1，∠FOP＝∠2.
(1)若∠1＝55°，求∠2的度数；
(2)求证：AE∥FP.
(1)【解】因为∠AOE＝∠1，∠FOP＝∠2，
又因为∠AOE＝∠FOP，
所以∠1＝∠2.
因为∠1＝55°，所以∠2＝55°.
(2)【证明】因为∠BAP＋∠APD＝180°，
所以AB∥CD，
所以∠BAP＝∠APC.
因为∠1＝∠2，
所以∠EAO＝∠FPO，
所以AE∥FP.INCLUDEPICTURE "节.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\节.TIF" \* MERGEFORMATINET
章末作业
一、选择题
1．下列图形中∠1和∠2互为对顶角的是( C ).
A． INCLUDEPICTURE "25Q-1.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-1.TIF" \* MERGEFORMATINET B． INCLUDEPICTURE "25Q-2.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-2.TIF" \* MERGEFORMATINET
C． INCLUDEPICTURE "25Q-3.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-3.TIF" \* MERGEFORMATINET D． INCLUDEPICTURE "25Q-4.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-4.TIF" \* MERGEFORMATINET
2．如图，点E在AC的延长线上，下列条件能判断AB∥CD的是( C ).
INCLUDEPICTURE "L26CGD7SX37.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX37.TIF" \* MERGEFORMATINET
A．∠D＝∠DCE
B．∠3＝∠4
C．∠1＝∠2
D．∠D＋∠ACD＝180°
3．下列语句中，不是命题的是( C ).
A．两点之间线段最短
B．对顶角相等
C．过直线AB外一点P作直线AB的垂线
D．不是对顶角不相等
4．如图，AB∥CD，若∠1＝65°，∠2＝120°，则∠3的度数为( B ).
INCLUDEPICTURE "25Q-6.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-6.TIF" \* MERGEFORMATINET
A．45° B．55°
C．60° D．65°
5．光线在不同介质中的传播速度是不同的，因此光线从空气斜射入水中要发生折射．物理课上，小军手持一激光笔射入水中，如图，水面与水杯下沿平行，光线从空气射入水中，发生折射，若∠1＝60°，∠ABO＝140°，则∠2的度数是( B ).
INCLUDEPICTURE "L26CGD7SX38.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX38.TIF" \* MERGEFORMATINET
A．10° B．20°
C．30° D．40°
6．将一个含30°角的三角尺和直尺如图放置，若∠1＝50°，则∠2的度数是( B ).
INCLUDEPICTURE "25Q-7.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-7.TIF" \* MERGEFORMATINET
A．30° B．40°
C．50° D．60°
7．如图，已知a∥b，则∠ACD的度数是( D ).
INCLUDEPICTURE "25Q-10.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-10.TIF" \* MERGEFORMATINET
A．45° B．60°
C．70° D．73°
二、填空题
8．命题“如果实数a，b满足a＞b，那么|a|＞|b|”的题设是____________________，它是________(选填“真”或“假”)命题．
【答案】实数a，b满足a＞b 假
9．如图，直线l分别与直线a，b相交，a∥b，若∠1＝71°，则∠2的度数为________．
INCLUDEPICTURE "25Q-12.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-12.TIF" \* MERGEFORMATINET
【答案】109°
10．如图，AB∥CD，EC⊥CD于点C，CF交AB于点B，若∠2＝30°，则∠1＝________°.
INCLUDEPICTURE "25Q-14.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-14.TIF" \* MERGEFORMATINET
【答案】60
11．如图，将一条对边互相平行的纸带进行两次折叠，折痕分别为AB和CD.若CD∥BE，∠1＝62°，则∠2的度数为________．
INCLUDEPICTURE "L26CGD7SX40.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX40.TIF" \* MERGEFORMATINET
【答案】68°
12．如图，将一副直角三角尺的其中两个顶点重合叠放(∠A＝30°，∠ABC＝60°，∠D＝∠BED＝45°).三角尺ABC固定不动，将三角尺DBE绕点B转动．当DE∥BC时，∠ABE的度数为________．
INCLUDEPICTURE "L26CGD7SX41.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX41.TIF" \* MERGEFORMATINET
【答案】75°或105°
13．如图，3条直线两两相交最多有3个交点，4条直线两两相交最多有6个交点，按照这样的规律，则10条直线两两相交最多有________个交点．
INCLUDEPICTURE "25Q-16.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-16.TIF" \* MERGEFORMATINET
【答案】45
三、解答题
14．如图，在正方形网格中，每个小正方形的顶点称为格点．利用不带刻度的直尺作图．
INCLUDEPICTURE "25Q-18.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-18.TIF" \* MERGEFORMATINET
(1)找一个格点D，过点C画AB的平行线CD；
(2)过点A画BC的垂线，垂足为E；
(3)线段AE与AC的大小关系是______(用“＜”号连接)，依据是_____________________________________________________________．
【答案】(1)图略
(2)图略
(3)AE＜AC 垂线段最短
15．如图，AB∥CD，CE⊥AD，垂足为E，若∠A＝38°，求∠C的度数．
INCLUDEPICTURE "25Q-20.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\25Q-20.TIF" \* MERGEFORMATINET
【答案】52°
16．如图，∠BAP＋∠APD＝180°，∠AOE＝∠1，∠FOP＝∠2.
INCLUDEPICTURE "L26CGD7SX43.TIF" INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\Administrator\\AppData\\Local\\Microsoft\\Windows\\INetCache\\Content.Word\\L26CGD7SX43.TIF" \* MERGEFORMATINET
(1)若∠1＝55°，求∠2的度数；
(2)求证：AE∥FP.
(1)【解】因为∠AOE＝∠1，∠FOP＝∠2，
又因为∠AOE＝∠FOP，
所以∠1＝∠2.
因为∠1＝55°，所以∠2＝55°.
(2)【证明】因为∠BAP＋∠APD＝180°，
所以AB∥CD，
所以∠BAP＝∠APC.
因为∠1＝∠2，
所以∠EAO＝∠FPO，
所以AE∥FP.
