Question 535096
This problem requires knowing that the sum of the interior angles in any triangle = 180 deg.  We are given the 3 angles for the triangle in terms of x:
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x
3x
x + 30
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We know they must sum to 180:
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x + 3x + (x + 30) = 180
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Combine like terms and simplify:
5x + 30 = 180
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Subtract 30 from both sides:
5x = 150
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x = 30 deg
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Cheers,
Lee