巳知:如图,在梯形ABCD中,AB=CD,AD∥BC,点E在AD上,且EB=EC. 求证:AE=DE.

问题描述:

巳知:如图,在梯形ABCD中,AB=CD,AD∥BC,点E在AD上,且EB=EC.
求证:AE=DE.

证明:∵EB=EC,
∴∠EBC=∠ECB,
又∵AD∥BC,
∴∠AEB=∠EBC,∠DEC=∠ECB,
∴∠AEB=∠DEC,
又∵∠A=∠D,EB=EC,
∴△ABE≌△DCE,
∴AE=CE.