Here's the question you clicked on:
Earthy
Find the measures of the complement and the supplement of each angle m<G= 79 degrees
supplementary angles add up to 180 degrees. So 180 - 79 = 101 degrees. complementary angles add up to 90 degrees. So 90 - 79 = 11 degrees.
so subtract by the main numbers? Can I use this method for all problems?
You can use it for problems that involve complementary & supplementary angles. If you are given one angle but don't know the other, just use this method.