Question

如图在三角请ABC中,AB=AC,BD垂直于AC于D,延长BC到E,似的CE=CD,并且BD=ED,说明AD=CE的理由

Answer 1

∵BD=DE∴∠DBC=∠DEC,

∵CD=CE∴∠CDE=∠DEC.∴∠DBC=∠DEC=∠CDE.

∵∠BCD=∠CDE+∠DEC=2∠DBC,BD⊥AC.

∴∠DCB=60º,∵AB=AC.

∴△ABC是等边三角形,∴BD垂直平分AC,AD=DC.

∴AD=CE.