| A | B |
|---|
| angle | two rays that meet at a common endpoint |
| ray | part of a line with one endpoint |
| line segment | part of a line with two endpoints |
| line | extends forever in both directions |
| right angle | measures exactly 90 degrees |
| acute angle | measures between 0 and 90 degrees |
| obtuse angle | measures more than 90 degrees and less than 180 degrees |
| straight angle | measures exactly 180 degrees |
| complementary angles | angles sum is equal to 90 degrees |
| supplementary angles | angles sum is equal to 180 degrees |
