Inequality Calculator

Solve linear and quadratic inequalities with step-by-step solutions

Remember:

When multiplying or dividing both sides of an inequality by a negative number, you must flip the inequality sign.

Solution regionx

Number line representation

Results

Enter values and click Calculate to see the result.

Theory & Formula

A linear inequality is similar to a linear equation, but instead of equality, it uses inequality symbols (<, >, ≤, ≥).

Key rules for solving inequalities:

  • Addition/Subtraction: Adding or subtracting the same value on both sides preserves the inequality
  • Multiplication/Division (positive): Multiplying or dividing by a positive number preserves the inequality
  • Multiplication/Division (negative): Multiplying or dividing by a negative number reverses the inequality
  • Solution set: An inequality typically has infinitely many solutions, represented on a number line or in interval notation
\(ax + b < c \rightarrow x < \frac{c - b}{a}\) (if \(a > 0\))

Worked Examples

Example 1

\(2x + 3 > 7 \rightarrow x > 2\)

Example 2

\(-3x + 5 \leq 14 \rightarrow x \geq -3\)

Example 3

\(5x - 2 < 13 \rightarrow x < 3\)

Interval Notation

\(x \geq 2\) is written as \([2, \infty)\)
Inequality Solver | MathCalcLab | MathCalcLab