Enter a slope and y-intercept to build the line's equation, and optionally evaluate y at any x.
How to Use the Slope-Intercept Form Calculator
Enter a slope (m) and y-intercept (b) to see the line's equation. Add an x-value to evaluate y at that point on the line.
equation: y = mx + b
at any x: y = m × x + b
x-intercept: x = −b ÷ mSlope-intercept form packs the two most useful facts about a line — how steep it is, and where it crosses the y-axis — into a single equation that can be read at a glance. Handing it a specific x-value turns it from a description of the whole line into a calculator for one point on it, which is the same thing a graphing tool does internally every time it plots a line pixel by pixel.