Question 1052134
Given angle 2 is congruent to angle 3 
Angle 1 and 2 are supplementary
Prove that the measure of angle one plus the measure of angle 3 = 180 
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2 = 3
1 + 2 = 180
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Substitute for "2"::
1 + 3 = 180
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Cheers
Stan H.
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