Question

What is the measure of B in the triangle?

This triangle is not drawn to scale

Answer 1

70 degrees

Explanation:

Answer 2

70°

Explanation:

(a) Calculate the value of x

∠A + ∠B + ∠C = 180

40 + 2x - 30 + x + 20 = 180

Combine like terms

3x + 30 = 180

Subtract 30 from each side

3x = 150

Divide each side by 3

x = 50

(b) Calculate m∠B

m∠B = 2x - 30 = 2×50 - 30 = 100 - 30 = 70°