The tickmarks on segments PR and PQ indicate they are congruent, ie PR = PQ. Because of this, the base angles R and Q (opposite the segments mentioned) are congruent
Angle R = Angle Q Since angle R is (2x+15) degrees, so is angle Q
Now use the idea that adding three angles of a triangle leads to 180 degrees P+Q+R = 180 x+(2x+15)+(2x+15) = 180 5x+30 = 180 5x = 180-30 5x = 150 x = 150/5 x = 30
If x = 30, then angle Q is angle Q = (2x+15) degrees angle Q = (2*x+15) degrees angle Q = (2*30+15) degrees angle Q = (60+15) degrees angle Q = 75 degrees