| A | B |
|---|
| point | an exact location on a line, ina plane, or in space |
| perpendicular lines | lines that intersect to form four right angles |
| line segment | part of a line that has two endpoints and all the points between them. |
| ray | part of a line that has one endpoint and continues without end in one direction |
| plane | a flat surface of points that continues without end in all directions. It is named by at least three points in the plane. |
| angle | two rays with the same endpoint |
| vertex | point at which two rays meet in an angle |
| degree | unit used to measure the size of an angle |
| right angle | an angle that measures 90 degrees and forms a square corner |
| acute angle | an angle that measures greater than 0 degrees and less than 90 degrees |
| obtuse angle | an angle that measures greater than 90 degrees and less than 180 degrees |
| straight angle | an angle that measures 180 degrees and forms a line |
| intersecting lines | lines that cross each other at exactly one point and form four angles |
| parallel lines | lines in the same plane that never intersect and are always the same distance apart |
| line | a straight path of points that continues without end in both directions. It has no endpoints. |
