| A | B |
|---|
| point | an exact location in space |
| line | a set of points that extends forever in 2 directions |
| collinear points | 3 or more points that lie in the same plane |
| non-collinear points | 3 or more points that do not lie in the same plane |
| ray | part of a line, it extends forever in one direction |
| endpoint | the point(s) at the end of a ray (or segment) |
| segment | a part of a line, it has 2 endpoints |
| plane | a flat surface that extends forever in all directions |
| parallel lines | lines that never meet |
| intersecting lines | lines that meet at a point |
| parallel planes | planes that never meet |
| intersecting planes | planes that meet, intersection is a line |
| skew lines | lines that are not parallel and never meet |
| perpendicular lines | lines that meet to form a right angle |
| midpoint | the point that divides a segment into 2 equal segments |
| congruent | same size and shape |
| congruent segments | segments that are the same length |
| angle | formed by two rays with a common endpoint |
| vertex | the common endpoint of the rays that form an angle |
| sides | the rays that form an angle |
| protractor | a tool for measuring angles |
| vertical angles | the non-adjacent angles formed by intersecting lines |
| complimentarty angles | two angles whose sum is 90 degrees |
| supplementary angles | two angles whose sum is 180 degrees |
| degrees | the unit of measure for angles |
| congruent angles | angles that have the same measure |
| right angle | an angle that measures 90 degrees |
| acute angle | an angle that measures less than 90 degrees |
| obtuse angle | an angle that measures more than 90 degrees but less than 180 degrees |
| straight angle | an angle that measures 180 degrees |
| adjacent angles | angles that share a side and an endpoint |
