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GCSE Algebra
Trial and Improvement
Learn trial and improvement 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 trial and improvement meaning confidently.
Use trial and improvement representations confidently.
Use trial and improvement methods confidently.
Use trial and improvement applications confidently.
Success checklist
✓I can explain what trial and improvement 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.