Question

若AB=CD=4cm,AE=5cm,则S△ACE=_____cm²,CE=____cm.

Answer 1

∵Rt△ABE≌Rt△CDE（已知AB＝CD,对顶角相等）,则CE＝AE＝5（对应边相等）.

BE＝DE＝3（对应边相等.勾股定理）；BC＝3＋5＝8.

∴△ACE面积＝Rt△ABC面积﹣Rt△ABE面积＝½（8×4﹣3×4）＝10cm²　．

CE＝5cm .