Measuring Angles - 4th grade

Recap from last week

Vertex

Ray

• a part of a line with one endpoint

• Where two rays meet

Delicious!

​What is a protractor?

A protractor is a tool we use in math to measure angles. It looks like this!

Time to put your thinking cap on.
This one’s tricky

This angle is less than 90°, this angle is very small

Acute angle

This angle often looks like the letter L. This will be the only angle with a square.

Right angle

Obtuse Angle

An obtuse angle is an angle that is greater than 90°, this angle is big.

This angle is a straight line, it measures 180°.

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