3(4x +12)=180
12x + 36 =180
-36. -36
180-36= 144
12x = 144
——. ——-
12. 12
X = 12
Answer:
x = 45
Step-by-step explanation:
Corresponding sides of similar triangles will be in same ratio.

Cross multiply
x*28 = 20*(x+18) {Use distributive method}
28x = 20x + 360
28x - 20x = 360
8x = 360
x = 360/8
x = 45
X=10
-3 on both sides
Then -6(x+4)+3 to the other side