Answer:
x = 100.5
Step-by-step explanation:
Supplementary angles are two angles that have a sum of 180°. THIS MEANS WE'RE ADDING.
We can use distributive property to solve this equation.
x + (x-21) = 180°.
x + x - 21 = 180°.
Now, we can combine like terms.
2x - 21 = 180.
Since there is a subtraction sign in front of the number 21, we do the opposite operation (addition).
Next, we add 21 to 180.
180 + 21 = 201.
2x = 201
Lastly, we divide 201 by 2.
The quotient is 100.5.
100.5 is the final answer.
Therefore, 100.5 is the value of x.
We can check our answer to make sure.
(100.5 - 21) + 100.5 =
79.5 + 100.5 = 180°.
