连接AE△ABE和△AFE中,已知:AB=EF,AF=BE,AE=AE∴△ABE≌△AFE(边边边),∴∠B=∠F△ABC和△EFC中,已知:AB=EF,∠B=∠F,∠ACB=∠ECF(对顶角相等),AB=EF∴△ABC≌△EFC(角边角)