Supplementary means the sum of two or more angles add up to 180 degrees. Since angle ∠1 is 58°, you need to subtract this number from 180 to find the supplement.
180-58= 122
Therefore, the measure of the supplement of ∠1 is 122°
We know that ∠1 measures 58 degrees. We want to find the measure of the supplement, which we can call x. Since they are supplementary, they should add to 180 degrees.
∠1 + ∠x = 180
58 + ∠x= 180
We are trying to find the supplement, also known as x. Therefore, we must isolate x.
58 is being added to x. The inverse of addition is subtraction. Subtract 58 from both sides of the equation.
