Two angles are supplementary supplementary if the sum of their measures is 180 degrees .180°. if the measure of an angle is 9 x9x degrees, represent the measure of its supplement supplement as an algebraic expression in x.

The answer is

Step-by-step explanation:

Two angles are supplementary if the sum of their measures is 180°. That means that two angles, let's say, α, and its supplement, β, are supplementary if the following is true:

Now, let's say that α measures 9x degrees, and let us replace in the above expression:

If we now want to represent the measure of the supplementary angle, β, we have to subtract 9x from both sides of the expression to get the final algebraic expression of β in x:

Note that an algebraic expression is just a mathematical relationship between numbers and variables! The goal was to isolate the supplementary angle, β, and find its relationship with the variable x.

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x