| A | B |
|---|
| Plane | a flat surface that extends forever in all directions |
| Line | a straight path of points that extend forever in opposite directions |
| Point | a dot that represents a location in a plane or in a space |
| Acute Angle | an angle that measures between 0° and 90° |
| Right Angle | An angle measuring exactly 90 degrees |
| Obtuse Angle | an angle that measures between 90° and 180° |
| Straight Angle | An angle measuring exactly 180 degrees |
| Complementary Angles | Two or more angles that may or may not be adjacent whose measures add up to 90 degrees |
| Supplementary Angles | Two or more angles which may or may not be adjacent whose measures add up to 180 degrees |
| Parallel lines | lines in the same plane that do not intersect |
| Perpendicular lines | Two lines that intersect to form four 90 degree angles. |
| Corresponding Angles | Angles formed by parallel lines and a transversal that are on opposite sides of the transversal and both are located in the same position but are on different lines which are parallel to one another. These angles are congruent. |
| line segment | part of a line consisting of two endpoints and all the points between them |
| ray | Part of a line that has one endpoint and extends forever in only one direction. Endpoints of rays are listed first. |
| Angle | two rays connected at their endpoints |
| vertex | the point at which the 2 rays of an angle meet |
| congruent | same measure |
| reflex angle | an angle that measures between 180° and 360° |
| transversal | The line that intersects two parallel lines |
| Vertical angles (vertically opposite) | The nonadjacent angles formed by 2 intersecting lines. the nonadjacent angles formed by 2 intersecting lines |
