Slope-Intercept Form Calculator

Calculate Slope-Intercept Form

Use this calculator to find the equation of a line in slope-intercept form (y = mx + b). Enter the required information based on what you know about the line.

How to Calculate Slope-Intercept Form

The slope-intercept form is a way of expressing the equation of a straight line. It's one of the most common and useful forms of a linear equation.

Slope-Intercept Formula

The slope-intercept form of a line is:

\[ y = mx + b \]

Where:

  • m is the slope of the line
  • b is the y-intercept (where the line crosses the y-axis)
  • x and y are the coordinates of any point on the line

Calculation Steps

  1. If you have two points:
    • Calculate the slope using the slope formula: m = (y₂ - y₁) / (x₂ - x₁)
    • Use one of the points and the calculated slope in the point-slope form
    • Rearrange to get the slope-intercept form
  2. If you have the slope and y-intercept:
    • Simply substitute the values into y = mx + b
  3. If you have a point and the slope:
    • Use the point-slope form: y - y₁ = m(x - x₁)
    • Rearrange to get the slope-intercept form

Example Calculation

Let's find the slope-intercept form of a line passing through the points (1, 2) and (4, 8).

  1. Calculate the slope: \[ m = \frac{8 - 2}{4 - 1} = \frac{6}{3} = 2 \]
  2. Use the point-slope form with (1, 2): \[ y - 2 = 2(x - 1) \]
  3. Expand: \[ y - 2 = 2x - 2 \]
  4. Rearrange to slope-intercept form: \[ y = 2x - 2 + 2 = 2x \]

Therefore, the slope-intercept form is y = 2x, with a slope of 2 and a y-intercept of 0.

Visual Representation

A visual representation can help understand these concepts better. Here's a diagram showing the line y = 2x:

X Y 1 2 -1 1 2 -1 (1, 2) (4, 8) y = 2x slope = 2

This diagram illustrates the line y = 2x, showing its slope and how it passes through the points (1, 2) and (4, 8).