1. Measuring Angles

2. To measure an angle, you need to use an instrument called a protractor.

3. How to use a protractor There are lines and numbers on the protractor.
Place the vertex of your angle on the hole in the bottom of the protractor.
Then place one ray of the angle at the 0-degree line.
Look where the other ray crosses the protractor. It has two numbers: one is less than 90 degrees and one is more than 90 degrees.
How to use a protractor

4. Let’s try it.
Place the protractor over the vertex of the angle so the vertex is at the center point on the bottom.
Align the bottom ray with the bottom of the protractor.
This angle is 125 degrees.
Try one on your own.
Here is an angle with the protractor placed over the angle.

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