An angle is formed by two rays sharing an endpoint, and it is measured in degrees by how far one ray is turned from the other. A full turn is 360 degrees and a right angle is 90.
Math Dictionary / Angle
Angle
An angle is formed by two rays that share the same endpoint.
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What it means
The shared endpoint is the vertex, and the opening between the rays is the angle.
Also called: angle measure
Examples
| A right angle measures 90 degrees |
| A straight angle measures 180 degrees |
| An acute angle is less than 90 degrees |
Common mistake
Do not call the side length of a shape an angle. An angle measures a turn or opening.
Try one
Question: What is the measure of a right angle?
Show answer
90 degrees.