Question

在三角形ABC中,角A=60度,AD是角BAC的角平分线,且AC=AB+BD,则角B=

Answer 1

延长AB到E,使EB=DB,那么AE=AC,AD是EC的垂直平分线,

∠ABC=2∠AED

∠AED=∠ACD

所以∠ABC=2∠ACB

∠ABC+∠ACB=180°-60°=120°

所以∠ABC=80°请采纳回答