1. 7.3 Angles and their measures

2. Definitions  Angle-A geometric figure consisting of 2 rays with a common endpoint  Vertex-The common endpoint of rays  Ray-Side of an angle  Measure of an angle-The side of an angle; measured in degrees  Protractor-Tool used to measure angles  Right angle-90 degree angle

3. More Definitions  Acute angle-An angle less than 90 degrees but greater than 0  Obtuse angle-Angle greater that 90 degrees but less than 180 degrees  Straight angle-180 degree angle

4. Ex 1: Name A B C BAC CAB l A Vertex always has to be in the middle

5. Ex. 2: What are the restrictions on X if < A is acute ( 2x+8) A 0 2x+8 0 -8 2x > -8 22 -8 2x < 82 22 x > -4 X -4