How to Use to a Protractor

How to Use to a Protractor - How it Works - Video

Example 1:

Since the angle in questioned is an acute angle, we must count from the left side starting from 0°.

Now we cut protractor in half to focus on the just the numbers we need.

We add the red numbers, 35 and 45, which are half between 30 and 40 and 40 and 50 to help count.

Since 35 is the closest to the line, we count up to 37°.

Example 2:

Since the angle in questioned is an obtuse angle, we must count from the left side starting from 0°.

Now we cut protractor in half to focus on the just the numbers we need.

We add the red numbers, 115 and 125, which are half between 110 and 120 and 120 and 130 to help count.

Since 120 is the closest to the line, we count up to 122°.

Example 3:

Since the angle in questioned is an acute angle, we must count from the right side starting from 0°.

Now we cut protractor in half to focus on the just the numbers we need.

We add the red numbers, 35 and 45, which are half between 30 and 40 and 40 and 50 to help count.

Since 40 is the closest to the end line without going over 43, we count up to 122°. Or you can count down from 45° to get the same answer, as well.