IntroLines
Point-Slope Form
y − y₁ = m(x − x₁)
Overview
Point-slope form is perfect when you know a point and the slope, but not the y-intercept.
Domain
(-∞, +∞)
Range
(-∞, +∞)
Key Properties
1
(x₁, y₁) is a known point on the line
2
m is the slope
3
Convert to slope-intercept by solving for y
4
Useful for tangent lines
Key Insight
This form is derived directly from the definition of slope: m = (y−y₁)/(x−x₁).
Visualize Point-Slope Form
Interact with the graph and explore this curve in the analytic geometry visualizer.