(1)BD=CE
△BAD和△CAE中,AB=AC,AD=AE,∠CAE=∠BAD.△BAD≌△CAE
所以BD=CE
（2）∵△ABD≌△ACE
∴∠ABN=∠ACE
∵∠ANB=∠CND
∴∠ABN+∠ANB=∠CND+∠NCE=90°
∴∠CMN=90°
即BD⊥CE