This deep dive covers Method: How to Substitute within Simplifying Expressions for GCSE Mathematics. Revise Simplifying Expressions in Algebra for GCSE Mathematics with 11 exam-style questions and 5 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 9 of 19 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Method: How to Substitute
1
Write out the expression
Copy it exactly as given
2
Replace each letter with its value
Use brackets around the number, especially for negatives!
3
Follow BIDMAS to calculate
Brackets, Indices, Division/Multiplication, Addition/Subtraction
4
Write your final answer
Check it makes sense!
Practice questions for Simplifying Expressions
Which two terms are like terms?
Explain why 3x + 2x² cannot be simplified to 5x³.
Quick recall flashcards
Like Terms
Terms with same letter and power: 2x and 5x are like terms
Substitution
Replace each letter with its given value, then calculate