证明:
∵AD⊥AE
∴∠DAE=90
∵∠BAC=90
∴∠DAC=∠BAC-∠BAD=90-∠BAD,∠EAB=∠DAE-∠BAD=90-∠BAD
∴∠DAC=∠EAB
∵AB=AC,AD=AE
∴△ACD≌△ABE (SAS)