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Topic summary · Foundation · CIE Core

Inequalities summary

Inequalities use <,>,≤,≥<,>,\le,\ge. Solving mirrors equations, except multiplying/dividing by a negative reverses the sign.

Files: foundation-28 Inequalities handout.pdf · foundation-28 Inequalities handout answers.pdf · free public downloads · diagrams in the PDFs

Key learning points

  • Represent on a number line: open circle for <</>\gt, filled for ≤\le/≥\ge.
  • Reverse the inequality when multiplying or dividing by a negative.
  • Integer solutions: list values that satisfy the inequality.

Worked example 1 — Solve and reverse

Solve −2x>6-2x>6.

Working

x<−3x<-3

Dividing by a negative reverses the inequality.

Worked example 2 — Number line

Describe x≥2x\ge2 on a number line.

-5-4-3-2-1012345-3

Working

closed circle at 2, arrow right\text{closed circle at 2, arrow right}

Filled circle means included.

Worked example 3 — Both sides

Solve 3x−1≤2x+53x-1\le 2x+5.

Working

x≤6x\le6

Collect like terms.

Scaffolded Learning Sheet and answers (PDFs)

This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.