## Dictionary Definition

The Oxford English Dictionary defines a straight angle as "an angle of 180°."## Real Examples of Straight Angles

The angles below are all straight angles:## What's in a Name?

A straight angle is called straight because it forms a straight line.## Do a 180

A straight angle is half a revolution, it changes the direction to point the other way.The phrases "do a 180", "a complete 180" refers to someone who completely changes their mind or direction the other way.

## Two Right Angles

A straight angle is two right angles because 180° = 2 × 90°.## Supplementary Angles

Two angles are supplementary if they add up to a straight angle.## Drag and Drop Game

Here is a drag-and-drop game to help you learn about the types of angles.## You might also like...

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