In a triangle DeltaABC, AB and AC are extended and bisectors of exterior angles are drawn to intersect at O. Find the m/_CBO?

1 Answer
Jul 13, 2017

Please see below.

Explanation:

Let the figure appear as shown below.

enter image source here

Now m/_CBO=1/2/_CBP=1/2(m/_A+m/_ACB)

similarly m/_BCO=1/2/_BCQ=1/2(m/_A+m/_ABC)

adding the two

m/_CBO+m/_BCO=1/2(m/_A+m/_ACB+m/_ABC+m/_A)

= 1/2(180^@+m/_A)=90^@+1/2m/_A

and m/_BOC=180^@-(m/_CBO+m/_BCO)

= 180^@-(90^@+1/2m/_A)

= 90^@-1/2m/_A