Question

There are angles whose measures add to 180°. Their measures are: m A = 67°
m B = (2x + 20) °
°, and m C = x°. What is the measure of B? (1 point)
• 180°
• 62°
• 31°
• 82°

Answer 1

m A + m B + m C = 180°

Substituting in the given values:
67° + (2x + 20)° + x° = 180°

Combining like terms:
3x + 87° = 180°

Subtracting 87° from both sides:
3x = 93°

Dividing by 3:
x = 31°

Substituting x = 31° into m B = (2x + 20)°:
m B = (2(31) + 20)°
m B = 82°

Therefore, the measure of angle B is 82°.