| A | B |
|---|
| angle | two rays with a common endpoint |
| bisector | a line, segment, or ray that passes through the midpoint |
| collinear | belonging to the same line |
| congruent | same size, same shape |
| parallel lines | lines in the same plane that do not intersect |
| skew lines | non-coplanar lines |
| coplanar | belonging to the same plane |
| perpendicular lines | lines that meet to form right angles |
| intersection | points shared by two figures |
| postulate | a statement that is accepted without proof |
| theorem | a statement that can be proven |
| segment | part of a line with two endpoints |
| ray | part of a line with one endpoint |
| vertex | the common endpoint of two rays |
| right angle | measures exactly 90 degrees |
| obtuse angle | measures between 90 and 180 degrees |
| acute angle | measures between 0 and 90 degrees |
| straight angle | measures exactly 180 degrees |
