Answer:
x = 28
Step-by-step explanation:
Angles on a straight line = 180°
4x + 3 + 2x + 9 = 180
4x + 2x + 3 + 9 = 180
6x + 12 = 180
6x = 180 - 12
6x = 168
6x/6 = 168/6
