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put this solution on YOUR website!Supplementary angles add up to 180 degrees.

degrees.
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ABC + PQR = 180 degrees. The angles are supplementary.
ABC = 11*(PQR) Substitute this into the first equation.
11*(PQR)+PQR = 180
12*(PQR) = 180 Divide both sides by 12.
PQR = 15 degrees.
ABC = 11*(PQR)
ABC = 11*(15)
ABC = 165 degrees.