Slope measures how steep a line is by comparing vertical change to horizontal change. The numerator y2-y1 is the rise, and the denominator x2-x1 is the run.
⚠If x1 equals x2, the line is vertical and the slope is undefined.
How Slope Works
Slope describes the rate of change of a line. Positive slope rises left to right, negative slope falls, zero slope is horizontal, and undefined slope is vertical.
Rise
The vertical change between points.
Run
The horizontal change between points.
Positive Slope
The line rises as x increases.
Undefined Slope
A vertical line has no finite slope.
💡 Example: For (1,2) and (4,8), m=(8-2)/(4-1)=2.
Applications of Slope
Graphing LinesRate of ChangeRoad GradeLinear Models
Frequently Asked Questions
What is a slope calculator?▼
It finds the slope of a line from two points using rise over run.
What is the slope formula?▼
The slope formula is m = (y2-y1)/(x2-x1).
How do I use this slope calculator?▼
Enter two coordinate points and click Calculate to get the slope.
What if x1 equals x2?▼
The slope is undefined because the line is vertical.
Where is slope used?▼
Slope is used in graphing, road grade, rate of change, and linear equations.
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