Classifying Angles
There are three types of angles. They are classified by their
measures.
Acute angles have
measures that are greater than 0° and less than 90°.
Right angles have
measures of exactly 90°.
The red square in the corner of the angle is the symbol
used to indicate a right angle.
Obtuse angles have measures
that are greater than 90° and less than 180°.
Straight angles have
measures of exactly 180°.