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Linear Equation Calculator

Evaluate a straight-line equation y = mx + b for any x.

How it works Report a problem

Linear Equation Calculator

Fast and accurate dynamic equations

y = mx + b y = x + @ x =
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About the Linear Equation Calculator

Evaluate a straight-line equation y = mx + b for any x.

How to use the Linear Equation Calculator

  1. Enter the slope m, the intercept b and the value of x.
  2. Use Add Equation Field to work with more than one line.

Formula and method

y = m × x + b, where m is the slope and b is the y-intercept (the value of y when x = 0).

Worked example

With m = 2, b = 3 and x = 4, y = 2 × 4 + 3 = 11.

Tips

  • A positive slope rises left to right and a negative slope falls.
  • To solve for x, rearrange to x = (y − b) ÷ m.

Frequently asked questions

What is the y-intercept?
The point where the line crosses the y-axis, where x is zero.