In Fig. 8.62, lines AB and CD intersect at O. If ∠AOC + ∠BOE = 70° and ∠BOD = 40° find ∠BOE and reflex ∠COE.
Given that,
∠AOC + ∠BOE = 70o
And,
∠BOD = 40o
∠BOF =?
∠BOD = ∠AOC = 40o (Vertically opposite angle)
Given,
∠AOC + ∠BOE = 70o
40o + ∠BOE = 70o
∠BOE = 70o – 40o
= 30o
∠AOC and ∠BOC are linear pair angle
∠AOC + ∠COE + ∠BOE = 180o
∠COE = 180o – 30o – 40o
= 110o
Therefore,
∠COE = 360o – 110o
= 250o