Coterminal angles are two angles that are drawn in the standard position (so their initial sides are on the positive x-axis) and have the same terminal side like 110° and -250°

Another way to describe coterminal angles is that they are two angles in the standard position and one angle is a multiple of 360 degrees larger or smaller than the other. That is, if angle A has a measure of M degrees, then angle B is co-terminal if it measures M +/- 360n, where n = 0, 1, 2, 3, ...

- 45 ° and −315°
- 90° and 450°
- 180° and −180°
- 170° and −190°
- 100° and −260°
- 360° and 720°
- 360° and −360°