Question

you are given the measure of angle 4. You also know the following angles are supplementary: Angles 1 and 2, angles 2 and 3, angles 1 and 4. Explain how you can determine the measures of angles 1, 2, and 3.

Answer 1

If you are given the measure of angle 4, then we know angle 2 is equal since it is a vertical angle. The angle of a line is 180 degrees, so subtract the measure of angle 4 (and/or 2) which  will give you the angle measure for both angle 1 and 3, since those are also equal due to vertical angles. Hope that helped! :)