# How to use a protractor

Written by ehow contributor
• Share
• Tweet
• Share
• Email

A protractor is a tool that allows you to measure an angle or construct an angle of a given measure.

Skill level:
Easy

### Things you need

• Protractors
• Notebook Papers
• Pencils And Erasers

## Instructions

1. 1

Find the center hole on the straight edge of the protractor.

2. 2

Place the hole over the vertex, or point, of the angle you wish to measure.

3. 3

Line up the zero on the straight edge of the protractor with one of the sides of the angle.

4. 4

Find the point where the second side of the angle intersects the curved edge of the protractor.

5. 5

Read the number that is written on the protractor at the point of intersection. This is the measure of the angle in degrees.

1. 1

Use the straight edge of the protractor to draw a straight line. This line will form one side of your angle.

2. 2

Find the center hole on the straight edge of the protractor.

3. 3

Place the hole over one end point of the line you have drawn.

4. 4

Line up the zero on the straight edge of the protractor with the line.

5. 5

Make a mark at the number on the curved edge of the protractor that corresponds to the desired measure of your angle. For example, mark at 90 for a 90-degree angle.

6. 6

Use the straight edge of the protractor to connect the mark to the end point of the first line, forming an angle.

#### Tips and warnings

• There are 360 degrees in a circle.
• A straight line measures 180 degrees.
• The corner of a square measures 90 degrees. This is called a right angle.
• Angles that measure fewer than 90 degrees are called acute angles. Those measuring more than 90 degrees are called obtuse angles.

### Don't Miss

• All types
• Articles
• Slideshows
• Videos
##### Sort:
• Most relevant
• Most popular
• Most recent

By using the eHow.co.uk site, you consent to the use of cookies. For more information, please see our Cookie policy.