Enter two points and instantly get the slope and the line’s equation, in both slope-intercept and point-slope form.
Slope & Line Equation Calculator
How It’s Calculated
Slope m = (y₂ − y₁) / (x₂ − x₁) — the change in y divided by the change in x. Once you have m and one point, the point-slope form y − y₁ = m(x − x₁) gives the line directly; rearranging it gives the more familiar slope-intercept form y = mx + c.
Worked Example
For (1,2) and (4,8): m = (8−2)/(4−1) = 6/3 = 2. Using point (1,2): y − 2 = 2(x−1), which simplifies to y = 2x.
Frequently Asked Questions
Q: What does it mean if the slope is undefined?
The line is vertical — both points share the same x-coordinate, so there’s no defined "rise over run." The equation is simply x = (that x-value).
Q: What if the slope is 0?
The line is horizontal — y stays the same regardless of x.
Forms of a line is one of the most direct mark-scorers in 1st PUC Straight Lines. See how Daniel Classes teaches 1st and 2nd PUC Mathematics →