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GCSE Algebra
Expanding Double Brackets
Learn expanding double brackets as part of build algebra fluency from expressions and equations through graphs, functions, proof and curve work.
Key idea
Keep both sides balanced, use notation accurately, and check by substituting your answer back in.
What you will learn
Use expanding double brackets meaning confidently.
Use expanding double brackets representations confidently.
Use expanding double brackets methods confidently.
Use expanding double brackets applications confidently.
Success checklist
✓I can explain what expanding double brackets 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.