Common Core Math Vocabulary

Acute Angle - Definition with Examples

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What is an acute angle? 
In geometry, an acute angle is an angle which measures less than 90 degrees (90°).

Here, ∠PQR measures 45 degrees (45°) and thus, is an acute angle.

Acute angle

We can find an acute angle in a stapler, a pair of scissors, and in a geometric compass, around us.

Acute angles around us real life examples

  Fun Facts

  • All angles of an acute triangle are acute in measure.

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Acute angles are the small ones! You see!
They are always smaller than 90 degrees.

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Instead of handing out math geometry worksheets on angles, ask children to observe/spot things around them in which they can see acute angles. 

You can also ask them to make acute angles using their arms and fingers.

Acute angles real life activity


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