Angles that measure less than 90 degrees.
Angles that measure more than 90 degrees but less that 180 degrees.
An angle that is 180 degrees.
A angle that measures exactly 90 degrees.
Two angles in which the sum of their degrees add up to 90 degrees
Two angles in which the sum of their degrees add up to 180 degrees.
An angle which is more than 180 degrees but less than 360 degrees.