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Key Stage 3 Algebra
Inequalities
Use inequality symbols, solve simple inequalities and represent solutions on number lines.
Key idea
Keep both sides balanced, use notation accurately, and check by substituting your answer back in.
What you will learn
Use inequality notation confidently.
Use solving confidently.
Use number lines confidently.
Use integer solutions confidently.
Success checklist
✓I can explain what inequalities means.
✓I can choose a suitable method without being told.
✓I can show clear working and check my answer.
Worked example
Solve 3𝑥 + 5 = 20.
Step 1
Subtract 5 from both sides: 3𝑥 = 15.
Step 2
Divide both sides by 3.
Step 3
𝑥 = 5.
Answer
𝑥 = 5
Quick practice
Question 1
Simplify 4𝑥 + 3𝑥 - 2𝑥.
Question 2
Solve 2𝑥 - 7 = 11.
Question 3
Expand 5(𝑥 + 3).
Related resources
These are linked to the wider Algebra topic for now.