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Estimate, measure and compare angles using degrees. Construct angles using a protractor (ACMMG112)

Source: Australian Curriculum, Assessment and Reporting Authority (ACARA)

Measuring angles with a protractor

Angles are measured with a protractor. There are different kinds of protractors, and there are some things we need to keep in mind to measure with them accurately.

A protractor has one set of numbers for measuring angles from the right, and another set of numbers for measuring angles from the left. When we use a protractor, we place the centre point on the vertex of the angle with the baseline sitting on one of the arms of the angle, as shown below.

Each of these angles measures 50°.

Two protractors.
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