Answer:
x = 22, m<B = 88
Explanation:
1) Finding the missing side. This is called a supplementary angle.
A = 180 - 132
A = 48°
2) Solving for the x
Triangle: a + b + c = 180°
4x + 2x + 48 = 180
6x + 48 = 180
6x = 180 - 48
6x = 132
x = 132/6
x = 22
Your answers and the question are correct.
Proof:
4(22) + 2(22) + 48 = 180
88 + 44 + 48 = 180
180 = 180