已知AB‖DE,BC‖EF,D,C在AF上,且AD=CF,求證:△ABC≌△DEF.

已知AB‖DE,BC‖EF,D,C在AF上,且AD=CF,求證:△ABC≌△DEF.

證明:∵AB‖DE,BC‖EF∴∠A=∠EDF,∠F=∠BCA又∵AD=CF∴AC=DF∴△ABC≌△DEF.(ASA)