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.