Let the "other" angle be x. Then we can set up the equation: 2x + 60 + x = 180, because supplementary means that the angles add up to 180 degrees.
We get:
3x + 60 = 180
3x = 120
x = 40.
2(40) + 60 = 80 + 60 = 140.
So one angle is 140 degrees and the other angle is 40 degrees.
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Hope this helps!
==jding713==
