∵BF=DE∴BF-EF=DE-EF∴BE=DF△ABE与△CDF中∵BE=DF，AB=CD，AE=CF∴根据SSS定理，△ABE≌△CDF∴∠AEB=∠CFD∴∠AED=∠CFB∴根据内错角相等定理，AE//CF
ACBDF=0是什么
