Slope Definition: a plain-English explanation of what the term means, why it matters in math, and how it is used, followed by worked examples and practice questions so the definition turns into something you can apply.
Math Dictionary / Slope
Slope
Slope measures how steep a line is: the change in y divided by the change in x.
AlgebraGrade 8Algebra 1GEDSATACT
What it means
It is often described as rise over run.
Also called: rate of change, rise over run
Examples
| If rise = 6 and run = 3, slope = 2 |
| A horizontal line has slope 0 |
| A vertical line has undefined slope |
Common mistake
Use change in y over change in x, not x over y.
Try one
Question: What is the slope from (1, 2) to (4, 8)?
Show answer
Slope = (8 – 2) / (4 – 1) = 6/3 = 2.