How to use this calculator
- Enter the coordinates of the first point (x₁, y₁).
- Enter the coordinates of the second point (x₂, y₂).
- Results update instantly.
Formula
Slope is rise over run. The y-intercept follows from substituting one point into y = mx + b.
m = (y₂ − y₁) / (x₂ − x₁)
b = y₁ − m x₁
d = √((x₂ − x₁)² + (y₂ − y₁)²)
θ = atan2(y₂ − y₁, x₂ − x₁)
Example
- Points (1, 2) and (4, 8).
- m = (8 − 2) / (4 − 1) = 2; b = 2 − 2 × 1 = 0.
- Equation: y = 2x; distance = √(9 + 36) ≈ 6.708.
Frequently asked questions
What does a negative slope mean?
The line goes down from left to right: y decreases as x increases.
What is the slope of a vertical line?
Undefined, because the run (x₂ − x₁) is zero. Its equation is x = constant.
How is slope expressed as a grade?
Multiply the slope by 100 to get a percentage grade. A slope of 0.05 is a 5% grade.