Question 491306
    Two angles are supplementary. Find their measures if one of them is 20 less than three times the measure of the other.
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Let x = one angle
then 
180-x = second angle (supplement)
.
180-x = 3x-20
180 = 4x-20
160 = 4x
40 degrees = x
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second angle:
180 - x = 180-40 = 140 degrees
.
answer: 40 and 140 degrees