Question

如图，点A、F、C、D在同一直线上，点B和点E分别在直线AD的两侧，且AB＝DE，∠A＝∠D，AF＝DC．求证：BC∥EF．

                         

                                       

                                 

                                                 

Answer 1

证明：∵AF＝DC，∴AC＝DF，

又∵∠A＝∠D ，

∴AB＝DE，∴△ABC≌△DEF，

∴∠ACB＝∠DFE，∴BC∥EF．