Answer:
C = 135 Degrees
Why?
Great question. When it says that C and D are supplementary, that means they add up to a specific number in degrees. Supplementary indicates that the angle(s) add up to 180 degrees. In this case, since you already know D, and you know it HAS to equal 180, you would do 180 minus 45, which equals 135.
Further Confusion?
Feel free to message me! :D
