Created by Mrs. Eileen F. Young, Marshall Middle School Math Teacher
Notice these elements of a protractor:
90 degree mark at top
Center line at bottom
double row of numbers
Protractor: a tool used to measure angles
A protractor measuring a 39 degree angle
How to use a protractor:
Line up the vertex (point of angle) on the center line at bottom.
Make sure the bottom line of the angle is lined up straight with the bottom line of the protractor.
The other line will point to a number on the protractor.
If the angle is acute read the smaller number.
If the angle is obtuse read the larger number.
A protractor measuring a 140 degree angle
