| A | B |
|---|
| Vertical Angles | Two angles whose sides form two opposite rays |
| Linear Pair | Two adjacent angles whose noncommon sides are opposite rays |
| Complementary Angles | Two angles whose measures add up to 90 degrees |
| Supplementary Angles | Two angles whose measures add up to 180 degrees |
| Point | An exact location in space with no size or dimension |
| Line | Extends infinitely in both direction |
| Plane | Extends infinitely in all direction |
| Collinear Points | Points that lie on the same line |
| Coplanar Points | Points that lie on the same plane |
| Line Segment | Part of a line that consists of two points, called enpoints,a nd all points that are between the two endpoints |
| Ray | A part of a line that has an endpoint and then extends infinitely in the other direction |
| Intersect | To have one or more common points |
| Segment Addition Postulate | If B is between A and C, then AB+BC=AC |
| Angle | Two rays with the same initial point |
| Vertex | The initial point of an angle |
| Congruent Angles | Angles with the same measure |
| Acute Angle | An angle with measure less than 90 degrees |
| Right Angle | An angle with measure equal to 90 degrees |
| Obtuse Angle | An angle with measure greater than 90 degrees |
| Straight Angle | An angle with measure equal to 180 degrees |
| Adjacent Angles | Angles that share a vertex |
| Midpoint | A point that divides or bisects a segment |
| Bisect | To divide into two congruent segments |
| Segment Bisector | A segment, ray, line, or plane that intersects a segment at the midpoint |
| Angle Bisector | A ray that divides an angle into two adjacent angles that are congruent |
