Answer:
m<x = 48
m<y = 132
Explanation:
Since x and y are supplementary angles, that means their sum is 180 degrees.
And we are given that y is 12 less than 3 times the measure of x. With this information we can make a system of linear equations.
x + y = 180
y = 3x - 12
So now plug in the value of y into the first equation.
x + y = 180
x + (3x - 12) = 180
x + 3x = 192
4x = 192
x = 48
And then plug this computed value of x back into the first equation to find the measure of y.
x + y = 180
48 + y = 180
y = 180 - 48
y = 132
So the measures of the angles are as follows:
m<x = 48
m<y = 132
Cheers.