P=2x, Q=7x, R=3x Besar sudut p…

2x + 7x + 3x = 180
12x = 180
x = 180/12
x = 15

P = 2x = 2 x 15 = 30 derajat

2x + 7x + 3x = 180
              12x = 180
                  x = 15

P = 2x
P = 2 × 15
P = 30