Question 100417
Hello!

First, we represent the angle as x. That means the supplement is 2x.

Now, we will do the equation.
Equation:
2x+x=180  (because the sum of an angle and its supplement is 180)

Now, we will solve.
2x+x=180
3x=180
x=60

x=60
2x=120

Final Answer: the angle is 60 and its supplement is 120.

Is that clear?

Thank You!