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Need help! (For 50 points)

Need help! (For 50 points)-example-1
User AlanSTACK
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1 Answer

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Answer:

  • 168°

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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°
User Inerte
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