Angles

1. 90 degrees

1.1. right angle

2. types of angles

2.1. adjacent angle

2.1.1. Next to

2.2. right angle

2.2.1. 90 degrees

2.3. complementry

2.3.1. 2 angles that add up to 90

2.4. supplementry

2.4.1. two numbers that add up to 180 degrees

3. measuring

3.1. line up vertex with the middle one of the segment and the other line between 0 and 180 degrees