Direct students to use the inner scale if the angle opens to the right, and the outer scale if the angle opens to the left, so they can easily measure the angles.
Note that the middle letter denotes the vertex point of the angle. Angles can be measured using the inner or outer scale of the protractor. This complete guide on how to use a protractor includes several examples, an animated video mini-lesson, and a free worksheet and answer key.īefore we learn how to use the protractor tool to measure angles, let’s do a super quick review of angle notation (understanding this important skill will make learning how to use a protractor much easier).Īngle Notation: In geometry, an angle is denoted by the ∠ symbol and includes 3 consecutive letters which represent the three points that form the angle. Welcome to this free lesson guide where you will learn how to read a protractor and how to use it to measure angles.
