Two angles that are supplementary have a ratio of 7 to 5. what are their measures?

Supplementary angles are two angles whose measures add to 180 degrees.
7 + 5 = 12, so the angles cannot possibly measure 7 deg and 5 deg, but their measures are in a 7 to 5 ratio.
If we multiply both 7 and 5 by the correct number, we will get the measures of the two angles that are supplementary and in a 7 to 5 ratio.
Let the number be x.

7x and 5x are also in a 7 to 5 ratio.

7x and 5x are the measures of two supplementary angles, so their sum is 180.

7x + 5x = 180

12x = 180

x = 15

The number we were looking for is 15.

7x = 7(15) = 105
5x = 5(15) = 75

The angles measure 105 deg and 75 deg.

Add up all the sides