Inequality Solver

Solve linear, quadratic and absolute-value inequalities and get the answer as an interval and on a number line. Try “solve 3x − 7 ≥ 11”.

Try an example:

How the Inequality Solver works

  1. Solve like an equation, but flip the inequality sign whenever you multiply or divide by a negative.
  2. For quadratics, find the roots first, then test each region for the sign.
  3. Write the solution in interval notation and mark the endpoints open or closed.

Frequently asked questions

When do you flip the inequality sign?

Whenever you multiply or divide both sides by a negative number.

What is the difference between ( ) and [ ] in intervals?

Round brackets exclude the endpoint (< or >). Square brackets include it (≤ or ≥).

More Algebra calculators

Linear Equation SolverSolve one-variable equations with balancing steps. Quadratic Equation SolverFactoring, completing the square and the quadratic formula. System of EquationsSubstitution, elimination and matrix methods. Factoring & ExpandingFactor or expand polynomials and expressions. Polynomial DivisionLong division and synthetic division, remainder theorem. Exponential & Log EquationsSolve equations with powers and logarithms.

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MathMate can make mistakes. Please double-check important steps and calculations.