Question

in a quadrilateral CO and DO are the bisectors of angle C and angle D respectively prove that angle A+angle B=angle 2COD

Answer 1

Angle DAB + Angle ABC +Angle BCD +Angle CDA =360degree
=> Angle DAB + Angle ABC + 2(Angle OCD + Angle ODC) =360degree
=> Angle DAB + Angle ABC +2(180degree - Angle COD) =360degree
=> Angle DAB + Angle ABC - 2Angle COD =360degree - 360degree
=> Angle DAB + Angle ABC =2Angle COD (Proved)

Answer 2

its the shot of the answer with diagram so it will be easy to understand