Question

如图,已知△abd≌△ace,试证明：be=cd,∠dco=∠ebo.

Answer 1

（1）∵△ABD≌△ACE,

∴AD=AE,AB=AC,∠ABD=∠ACE

∴AD-AC=AE-AB, 180°-∠ABD=180°-∠ACE

即CD=BE,∠DCO=∠EBO

（2）∠ABD=180°-∠A-∠D=180°-43°-30°=107°