Acute Angles

Different Angles have different names:types of angle

An Acute Angle is less than 90°

This is an acute angle

All the angles below are acute angles:

Which Angle?

Remember to look carefully at which angle you are being asked to name:

The acute angle is the small angle which is less than 90°.

If you choose the larger angle you would
have a Reflex Angle instead:
  The smaller angle is an Acute Angle,
but the larger angle is a Reflex Angle