∠1 and angle, 2∠2 are supplementary angles. If m, angle, 1, equals, left bracket, 5, x, minus, 11, right bracket, degreesm∠1=(5x−11)

and m, angle, 2, equals, left bracket, 5, x, plus, 21, right bracket, degreesm∠2=(5x+21)

, then find the measure of angle, 1∠1.