


Related Terms 


Obtuse Angle: An obtuse angle is greater than 90 degrees but less than 180 degrees. 
Angle: Region between two rays or the amount of rotation about a fixed point.
Acute Angle: An acute angle is an angle whose measure is between 0 degrees and 90 degrees.
Degree of an Angle: A unit for measuring angles.
Protractor: A measuring device that can be used to approximate the measure of an angle.
Ray: A ray begins at a point and goes on forever in one direction.
Reflex Angle: An angle that measures more than 180 degrees, but less than 360 degrees.
Right Angle: An angle that measures exactly 90 degrees.
Straight Angle: A straight angle is formed by a straight line and measures exactly 180 degrees
Vertex of an Angle: The common endpoint of the two rays that serve as the sides of an angle.


