1. In Fig. 6.39, sides QP and RQ of PQR are produced to points S and T respectively. If SPR = 135° and PQT = 110°, find PRQ.
PQR is a triangle, SPR =, PQT =
Now, TQP + PQR = (Linear pair)
So, PQR =
Since the side of QP of the triangle, PQR is produced to S
So, PQR + PRQ = (Exterior angle property of triangle)