证明:在RTΔBAD和RTΔCAE中,BD=CE,AB=AC则RTΔBAD全等于RTΔCAE∴∠1=∠2在RTΔBAD和ΔCFD中∠1=∠2,对顶角也相等。∴∠BAD=∠CFD=90°∴BF⊥CE
证明:在RTΔBAD和RTΔCAE中,BD=CE,AB=AC则RTΔBAD全等于RTΔCAE∴∠1=∠2在RTΔBAD和ΔCFD中∠1=∠2,对顶角也相等。∴∠BAD=∠CFD=90°∴BF⊥CE谢谢