Question

OB是角ABC的平分线，OD是∠ADC的平分线，∠A=21°，∠O=43°，∠C度数？

急啊，急啊，速度速度！步骤要齐全！
这是图

Answer 1

∠O+1/2∠D=∠A+1/2∠B∠O+1/2∠B=∠c+1/2∠D∠O+1/2∠D+∠O+1/2∠B=∠A+1/2∠B+∠c+1/2∠D2∠O=∠A+∠c∠C=2∠O-∠A=43×2-21=65答案补充
∠O+1/2∠D=∠A+1/2∠B∠O+1/2∠B=∠c+1/2∠D∠O+1/2∠D+∠O+1/2∠B=∠A+1/2∠B+∠c+1/2∠D2∠O=∠A+∠c∠C=2∠O-∠A=43×2-21=65

Answer 2

∠O+1/2∠D=∠A+1/2∠B ∠O+1/2∠B=∠c+1/2∠D ∠O+1/2∠D+∠O+1/2∠B=∠A+1/2∠B+∠c+1/2∠D 2∠O=∠A+∠c ∠C=2∠O-∠A=43×2-21=65

Answer 3

32