WORKING WITH ANGLE MEASURES
|Vertical angles are the opposite angles formed by the intersection of two lines, line segments, and/or rays.|
In the image [right], angles 1 and 4 are vertical angles, and angles 2 and 3 are vertical angles.
Vertical angles have the same measure.
|A linear pair is two adjacent angles which form a straight angle.|
The sum of the two angle measures is 180°.
In the image [right], angles 1 and 2 form a linear pair.
Supplementary angles are two angles whose measures sum to 180°.
Complementary angles are two angles whose measures sum to 90°.