Q3 of 95 Page 14

In a quadrilateral ABCD, CO and DO are the bisectors of ∠C and ∠D respectively. Prove that ∠COD = (∠A+∠B).

Given,


In quadrilateral ABCD,


CO is the bisector of ∠C


DO is the bisector of ∠D


In ΔCOD



⇒ ∠COD =


⇒ ∠D+∠C = 360 – (∠A+∠B)


SO,


⇒ ∠COD =


⇒ ∠COD = (∠A+∠B) Proved.


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