Answer:
180 (I'm just realizing now that I didn't have to do all that work but here you go)
Explanation:
18 + x + 4x - 3 = 180
5x + 15 = 180
- 15 - 15
5x = 165
/ 5 / 5
x = 33
18 + x + 4x - 3 = 180
18 + 33 + 4 (33) - 3 = 180
51 + 132 - 3 = 180
180 = 180