Answer:
2x + 60 = 4x( Vertically opposite angle)
60 = 4x - 2x
4x - 2x = 60
2x = 60
x = 60÷2
x = 30
2x + 60 + B = 180° ( Linear Pair )
2(30) + 60 + B = 180°
60 + 60 + B = 180°
120 + B = 180°
B = 180° - 120
B = 60
