How many degrees are in a straight angle?

A straight angle measures exactly 180 degrees. This type of angle is formed when two rays point in opposite directions, creating a straight line. In the context of geometry, it is important to recognize how various angles are defined in relation to one another.

A right angle, for example, measures 90 degrees, which is a quarter of a full rotation, while a full circle represents 360 degrees. An obtuse angle measures more than 90 degrees but less than 180 degrees, which doesn't apply in this instance. Hence, it is clear why the measure of a straight angle, defined by its relationship to a line and the full rotation of angles, is precisely 180 degrees.