题目

如图1,等腰Rt△ABC中,∠A=90°,点D,E分别在边AB,AC上,AD=AE,连接DC,点M,P,N分别为DE,DC,BC的中点.(1)观察猜想:图1中,线段PM与PN的数量关系是,位置关系是;(2)探究证明:把△ADE绕点A逆时针方向旋转到图2的位置,连接MN,BD,CE,判断△PMN的形状,并说明理由;(3)拓展延伸:把△ADE绕点A在平面内自由旋转,若AD=8,AB=20,请直接写出△PMN面积的最大值.根据短文内容,判断对(T)错(F)My name is Xiaoyong. I'm nine. I'm a pupil. I get up at seven o'clock. I go to school at eight o'clock. I go home at four o'clock. I watch TV at six o'clock. I go to bed at nine o'clock.(1)I get up at seven o'clock.(2) I go home at five o'clock.(3)I go to bed at half past nine.(4)I watch TV at half past six.
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