If an angle in a right triangle measures $x$ degrees, what is the measure of its supplement?

• A. $180-x$ degrees
• B. $90-x$ degrees
• C. $90+x$ degrees
• D. $x$ degrees

Answer: (A)

Verified step by step guidance

1. Recall that the supplement of an angle is defined as the angle that, when added to the original angle, equals 180 degrees. This is because supplementary angles sum to 180 degrees.
2. Given the angle measures \(x\) degrees, set up the equation for the supplement angle \(S\) as \(x + S = 180\) degrees.
3. To find the supplement \(S\), isolate it by subtracting \(x\) from both sides of the equation, resulting in \(S = 180 - x\) degrees.
4. Note that this relationship holds for any angle \(x\), regardless of whether it is part of a right triangle or not.
5. Therefore, the measure of the supplement of an angle measuring \(x\) degrees is \$180 - x$ degrees.