Correct option is A
Given:
In , the bisectors of and meet at point O . It is given that . We need to find the measure of .
Theorem Used
In a triangle, if two angle bisectors intersect at a point, that point divides the included angle between the other two vertices. For a triangle with internal angles A, B, and C , the measure of the angle at the intersection of the bisectors of B and C () is given by:
Solution
Substitute the value of into the formula:
The measure of .