Question

Need help! (For 50 points)

Answer 1

• 168°

------------------------------

Supplementary angles add up to 180°:

• m∠A + m∠B = 180°

Substitute and solve for x:

• x - 9 + 7x + 21 = 180
• 8x + 12 = 180
• 8x = 168
• x = 21

Find the measure of ∠B:

• m∠B = (7*21 + 21)° = 168°