| Term | Definition |
| equation of a horizontal line | y=# |
| equation of a vertical line | x=# |
| slope of a horizontal line | 0 |
| slope of a vertical line | undefined |
| parallel lines | have equal slopes |
| relations | a set of ordered pairs (points) |
| function | a relation in which each input has exactly one output (x=input, y=output) |
| domain | the set of all input values |
| range | the set of all output values |
| perpendicular lines | have opposite and reciprocal slopes |
| standard form | Ax+By=C |
| point-slope form | y-y1=m(x-x1) |
| slope-intercept form | y=mx+b |
| function notation | f(x)=_x+ or -_ |