| A | B |
|---|
| acute angle | An angle with measure between 0 degrees and 90 degrees |
| angle | Consists of two rays with the same endpoint. The rays are the sides and the endpoint is the vertex. |
| collinear points | Points that lie on the same line |
| congruent angles | Angles that have the same measure |
| congruent segments | Segments that have the same length |
| conjecture | An unproven statement that is based on a pattern or observation |
| coordinate | The real number that corresponds to a point on a line |
| coplanar lines | Lines that lie on the same plane |
| coplanar points | Points that lie on the same plane |
| counterexample | An example that show that a conjecture is false |
| degrees | The units that are used to measure angles |
| distance | The absolute value of the difference of the coordinates of the two points on a line |
| endpoint | A point at the boundary of line segment or ray |
| inductive reasoning | A process that includes looking for patterns and making conjectures |
| intersection | The point or points that two or more figures have in common |
| length | The distance between the endpoints of a segment or two points on a line |
| line | A straight arrangement of points that extends infinitely in both directions |
| obtuse angle | An angle with measure between 90 degrees and 180 degrees |
| plane | A flat surface that has no thickness that extends in all directions and has length and width but no thickness |
| point | Names location and has no size |
| postulate | A statement that is accepted without proof |
| ray | Part of a line, with one endpoint, and extending to infinity in one direction |
| right angle | An angle with measure 90 degrees |
| segment | Two points on a line and all the points between them |
| straight angle | An angle with measure of 180 degrees |
| undefined term | Words such as point, line and plane that are not mathematically defined using other known words |
| vertex of an angle | The point on an angle where the two sides intersect |
