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Geometry: Acute Angles and Obtuse Angles

Definition:
The difference between acute and obtuse angles is really just a matter of vocabulary. There is very little mathematical understanding invoved with learning the difference between the two. Any angle which is more than 0 and less than 180 falls into one of the following three categories (regardless of how the angle is rotated or oriented):

Any angle which is: Greater than 0° and less than 90° is an acute angle Acute Angle Examples:		Any angle which is: Equal to exactly 90 is a right angle Right Angle Examples:		Any angle which is: Greater than 90 and less than 180 is an obtuse angle Obtuse Angle Examples:

A few things should be noted about acute, right, and obtuse angles:
   - A 90° angle is NOT an acute angle and it is NOT an obtuse angle - it is a right angle
   - A 0° angle is a LINE and is NOT an acute angle
   - An angle that is GREATER than or EQUAL to 180° is NOT an obtuse angle

Hint: To remember the names, think that something "cute" is small (like a puppy). Therefore, an "acute" angle is a small angle.