| A | B |
|---|
| acute angle | an angle that measures less than 90 degrees. |
| alternate exterior angles | equivalent angles found on the outside of two parallel lines on opposite sides of a transversal |
| alternate interior angles | equivalent angles found on the inside of two parallel lines on opposite sides of a transversal |
| complementary angles | a pair of angles that share one leg. The sum of these two angles measures 90 degrees. |
| obtuse angle | an angle that measures more than 90 degrees. |
| parallel lines | two lines that lie in the same plane that will never cross when extended |
| perpendicular lines | lines in the same plane that intersect at 90 degrees |
| right angle | a 90 degree angle |
| supplementary angles | a pair of angles that share one leg. The sum of these two angles measures 180 degrees. |
| transversal | a line that cuts across two parallel lines |
| vertical angle | Equivalent opposite angles formed by two intersecting lines (e.g., the top and bottom angles of an “X.” Vertical angles share a common vertex. |
| alternate interior angles | Picture,  |
| alternate exterior angles | Picture,  |
| vertical angles | picture,  |
| parallel lines | picture,  |
| perpendicular lines | picture,  |
