Question

在矩形ABCD中,AE平分∠DAC,DH⊥AC于H交AE于点F,过F作FG‖AC交CD于点G,求证:(1)DE=

Answer 1

1、证明：过点F作FM⊥AD于M,过点G作GN⊥AC于N∵AE平分∠DAC∴∠CAE＝∠DAE∵DH⊥AC,FM⊥AD,AF＝AF∴△AHF全等于△AMF∴HF＝MF∵DH⊥AC,GN⊥AC,FG∥AC∴矩形HFGN∴HF＝GN∴GN＝MF∵DH⊥AC∴∠ACB+∠CDH＝90∵矩形ABCD...