设未知数,局仔
设∠AOB为X则∠BOC为桐旁汪2X,∠DOE为Y则∠COD为2Y,
∠BOD=∠BOC+∠COD=2X+2Y
由题启衫可知,X+2X+Y+2Y=120
3X+3Y=120
X+Y=40
所以∠BOD=∠BOC+∠COD=2X+2Y=2(X+Y)=80
几厅虚何:
∠BOC=2/3*∠AOC
∠COD=2/则伏亩3*∠COE
∠BOD=∠BOC+∠COD=2/3∠AOC+2/3∠COE=2/孙森3∠AOE=2/3*120°=80°
解:设∠AOB=x°,则∠BOC=2x°,
设橘洞罩∠DOE=y°,则∠COD=2y°
因为颤拍∠圆闹AOE=120°,所以∠AOE=∠AOB+∠BOC+∠DOE+∠COD
=x+2x+Y+2y=3x+3y=120°
所以x+Y=40°
所以∠BOD=∠BOC+∠COD=2x+2y=80°