Estimate Measure and Compare Angles Using Degrees (5)

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

LO: To estimate, measure and compare angles using degrees.
To construct angles using a protractor.

Know:

  • That angles are measured using degrees.

Understand:

  • That angles can be measured using degrees
  • That angles can be constructed using a protractor.

Do:

  • I can draw and measure angles using a protractor.

A right angle always adds up to 90 degrees. So all 90 degree angles are right angles. You can always tell that angles are right angles if they have a little square between the arms of the angle.

Anything less than (smaller) a 90 degree angle is called an acute angle.

If the angle is larger (bigger) than a 90 degree angle, then the angle is called an obtuse angle.

If the angle is a lot larger (bigger) than a 90 degree angle, then the angle is called an reflex angle.

In Maths, we use a protractor to help us draw angles. Notice how a protractor has 2 sets of numbers (inside and outside). This is where you have to think in order to determine which set of numbers you are going to use.

Teaching Ideas

Using Protractor Videos

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