| A | B |
|---|
| point | position in space |
| straight line | an infinite series of points |
| line segment | a part of a straight line |
| horizontal line | a straight line that lies in a left-to-right position |
| vertical line | a straight line in an up-and-downn position |
| oblique line | straight line in a slanting position |
| parallel lines | straight lines that do not intersect at any point |
| perpendicular lines | two lines forming right angles where they intersect |
| congruent segments | segments that are equal in length |
| collinear points | points on the same line |
| postulates | statements that are accepted as true without proof |
| plane | a particular se t of points suggested by a flat surface |
| coplanar points | points on the same plane |
