Angle PRQ=e (Vertically opposite angles) Sum of angles in a triangle is 180∘ 50+38+PRQ=180 88+PRQ=180 PRQ=180−88 PRQ=92 But angle PRQ=e=92 132+ angle RTS=180 (Sum of angles on straight line is 180∘ ) Angle RTS = 180−132 Angle RTS=48 e+d+ Angle RTS=180 Sum of angles in a triangle is 180° e=92 92+d+48=180 d+140=180 d=180−140 d=40∘