Linear Inequalities

Solve like an equation, but flip the sign when you multiply or divide by a negative.

Solve as usual, then flip the inequality when multiplying or dividing by a negative.
On a number line, use an open circle for < or > and a closed one for ≤ or ≥.
Compound inequalities such as 1 < 2x − 3 < 9 are solved in one chain.
Test a value to check.

Watch out: Not flipping the sign after dividing by a negative.

Worked example

Solve −2x + 3 > 11.

Answer: x < −4

Try it yourself

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