Imagine you're buying apples at a market. You don't know how many you'll buy yet, so instead of writing "cost = 50p × ???", you write "cost = 50p × n" where n is the number of apples. That's algebra! Letters are placeholders for numbers we don't know yet - they're like empty boxes waiting to be filled.
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This introduction covers Why Use Letters? within Algebraic Notation for GCSE Mathematics. Revise Algebraic Notation in Algebra for GCSE Mathematics with 13 exam-style questions and 4 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 1 of 7 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Algebraic Notation
In the expression 7x, what is the coefficient?
Explain the difference between an equation and an identity. Give one example of each.
Quick recall flashcards
Term
A single part of an expression: 3x is one term
Variable
A letter representing an unknown value