Let one angle be x.
The other angle will be (x + 30).
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Supplementary angles add up to 180:
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x + x + 30 = 180
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Combine like terms:
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2x + 30 = 180
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Take away 30 from both sides:
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3x = 150
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Divide by 3 on both sides:
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x = 50
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Answer: The smaller angle is 50°
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