2道1.如图1,点B、F、C、E在同一直线上,FB=CE,AB‖ED,AC平行FD 求证AB=DE,AC=DF2.如图2

1．证。 如图1, ∵AB‖ED,AC‖FD, ∴∠ABC＝∠FED,∠ACB＝∠DFC。               ∵ FB=CE,∴FB+FC= CE+FC,即 BC=FE。               由上知 △ABC≌△DEF, ∴AB=DE,AC=DF。2．证。 如图2, ∵FC‖AB,∴∠ADE＝∠CFE,               又∠AED＝∠CED,且已知AE＝CE,∴△ADE≌△CEF,               于是AE＝CE得证。