in a triangleABC the sides AB and AC ac are produced to P and Q respectively. the bisectors of anglePBC and angleQCB intersect at a point O. prove that angleBOC = 90-12 angle A

in a triangleABC the sides AB and AC ac are produced to P and Q respectively. the bisectors of anglePBC and angleQCB intersect at a point O. prove that angleBOC = 90-12 angle A