如图,若BE和CF△ABC的角平分线,∠ABC=70°,则∠AOC是多少度

125°
∠AOC=∠EOC+∠AOC
根据外角定理得
=1/2∠A+1/2∠C+∠B
=1/2∠A+1/2∠C+1/2∠B+1/2∠B
=90度+1/2∠B=90+35=125°

因为∠BAC+∠ACB=180°-∠ABC=180°-70°=110°
∠AOC=∠AOE+∠COE
因为∠AOE=∠ABO+∠OAB=∠ABC/2+∠BAC/2
∠COE=∠OBC+∠OCB=∠ABC/2+∠ACB/2
所以∠AOC=∠AOE+∠COE =（∠ABC/2+∠BAC/2）+（∠ABC/2+∠ACB/2）
=∠ABC+（∠BAC+∠ACB）/2
=70°+110°/2
=135°

∠AOC=90度+1/2*∠B=90+35=125°

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125