Step-by-step explanation:
6x° = (2x + 3)° + 77° (Exterior angle of a triangle = sum of two interior angle )
6x = 2x + 3 +77
subtract 2x from both sides
6x - 2x = 2x - 2x + 3 + 77
4x = 3 + 77
4x = 80
therefore:
x = 20°
angle PQR = 120°
angle RSQ = 43 i.e [(2 x 20) + 3)]
