The measure of an angle is 12 less than two times the complement. find half the supplement

56 degrees

Let x be the complement
Then the measure of the other angle is just 2x - 12
And they sum to 90 degreesso we have
x + 2x - 12 = 90
3x - 12 = 90 add 12 to both sides
3x = 102 divide by 3 on both sides
x = 34 degrees and that's the measure of the complement
Then ...2*34 - 12 = 68 - 12 = 56 degrees