Khan Academy Supplementary Angles

1. Supplementary Angles

1.1. They are two angles which add up to 180 degrees

1.1.1. 180 degrees is also called a straight angle

1.2. The outside of the angles add up to 180 degrees

1.2.1. For example, if there are two angles in a circle out of four and both of them look almost the same size and one of the angle's degrees is given as 80 degrees, then the other one can not be10 degrees to equal 90 because it look almost the same size as the 80 degrees angle. So you have to subtract 80 by 180 which will give you 100, so your other angle will be 100 degrees making both of the angles supplementary

2. Complementary Angles

2.1. They are two angles which add up to 90 degrees

2.2. The outside of the two angles make up a right angle (90 degrees)

2.2.1. Which makes them adjacent

2.2.1.1. Adjacent meaning two adjacent angles that share the same line/ray and vertex