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Key Stage 3 Algebra
Simplifying Expressions
Collect like terms, use coefficients correctly and simplify expressions with powers.
Key idea
Keep both sides balanced, use notation accurately, and check by substituting your answer back in.
What you will learn
Use like terms confidently.
Use coefficients confidently.
Use powers confidently.
Use notation confidently.
Success checklist
✓I can explain what simplifying expressions 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.