An angle measures 12 degrees less than 3 times its supplement

Given that the angle measures 12 degrees less than 3 times the supplement, the size of the angle will be:

suppose the size of the supplement is x;

the size of the angle supplementary to x will be:

3x-12

Given that the sum of supplementary angles is 180, thus;

x + (3x-12) = 180

solving for x we get:

4x-12=180

4x=180+12

4x=192

x=192/4

x=48

the size of the supplementary angles will be:

48*3-12

=132