| A | B |
|---|
| angle | two rays with a common endpoint |
| acute angle | an angle less than 90 degrees |
| right angle | an angle measuring 90 degrees |
| obtuse angle | an angle more than 90 degrees |
| straight line | 180 degrees |
| vertical angles | angles formed by two intersecting lines |
| congruent | same size, same shape |
| alternate interior angles | angles inside parallel lines, and on opposite sides of the transversal |
| alternate exterior angles | angles outside parallel lines and on opposite sides of the transversal |
| supplementary angles | two angles that add to 180 degrees |
