Question

（本题10分）（1）如图1，已知∠AOB，OA＝OB，点E在OB边上，四边形AEBF 是平行四边形，请你只用无刻度的直尺在图中画出∠AOB的平分线．（保留作图痕迹，不要求写作法）
（2）如图2，在10×10的正方形网格中，点A（0，0）、B（5，0）、C（3，6）、D（－1，3），
①依次连结A、B、C、D四点得到四边形ABCD，四边形ABCD的形状是    ▲     .
②在x轴上找一点P，使得△PCD的周长最短（直接画出图形，不要求写作法）；
此时，点P的坐标为    ▲     ，最短周长为    ▲     .

Answer 1

解：（1）如图所示；······································································ 2分
（2）①等腰梯形；·············································································· 4分
②P（，0）·············································································· 6分
（其中画图正确得2分）··················································· 10分
 

略