Math

Absolute Value Equation Calculator

Solve |ax + b| = c over the real numbers, including zero and degenerate cases.

Exact method explained belowEditable inputs
Calculation notebook
Calculation notebook

The formula and worked example below explain the calculation.

See the method

Enter your values

Runs on your device

Your answer

Your result

Let’s calculate.

Use the Calculate button to see your result.

Review the method below for assumptions and conventions.

How to use this tool

  1. Enter coefficient a, constant b, absolute value target c.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

The method, explained

For c ≥ 0, solve ax+b = c and ax+b = −c and remove duplicate roots. If c < 0 no real solution exists because absolute values are nonnegative.

A WORKED EXAMPLE

Using coefficient a = 2, constant b = -3, absolute value target c = 5, the result is x = -1 x = 4. Change these example inputs to match your task; use the method above to check each step.

Understanding your result

A positive target can be reached when the inner expression equals either the positive target or its negative. A zero target produces just one root when a is nonzero.

What to keep in mind

Numeric linear expression inside a single absolute value. Finite-precision arithmetic is used. Check the domain and the stated convention before using an approximation.

Common questions

Why can there be two answers?

A positive target can be reached when the inner expression equals either the positive target or its negative. A zero target produces just one root when a is nonzero.

How can I check the result?

For c ≥ 0, solve ax+b = c and ax+b = −c and remove duplicate roots. If c < 0 no real solution exists because absolute values are nonnegative. The worked example uses editable inputs. Calculations run on your device; no external API or account is required.

Methodology maintained by ClarityKit. How these tools are built and checked.