| A | B |
|---|
| acute angle | measures less than 90 |
| right angle | measures 90 degrees |
| obtuse angle | measures more than 90, less than 180 |
| congruent | has equal measure |
| midpoint | divides segment into two equal parts |
| angle bisector | divides angle into two equal angles |
| acute triangle | has all 3 acute angles |
| obtuse triangle | has one obtuse angle |
| right triangle | has one right angle |
| scalene triangle | has no equal sides |
| isosceles triangle | has two equal sides |
| equilateral triangle | has all three equal sides |
| equiangular triangle | has all three equal angles1 |
| complementary angles | two angles that add up to 90 |
| supplementary angles | two angles that add up to 180 |
| adjacent angles | two angles next to each other |
| linear pair | two angles that form a line |
| vertical angles | angles formed by intersecting lines |
| perpendicular lines | lines that form right angles |
| perpendicular bisector | forms right angles and cuts into two equal parts |
| parallel lines | coplanar lines that do not intersect |
| skew lines | noncoplanar lines |
| alternate interior angles | angles on alternate sides of a transversal inside parallel lines - congruent |
| alternate exterior angles | angles on alternate sides of transversal, outside parallel lines - congruent |
| corresponding angles | angles in same position of "hub" formed by transversal and parallel lines - congruent |
| same side interior angles | angles on same side of transversal, inside parallel lines - supplementary |
