Variable: GCSE Maths Definition

What is a variable?

In GCSE maths a variable is a symbol, usually a letter such as or , that is used to represent a value or quantity that can change.

In algebra, variables are used as part of a term or expression to represent unknown numbers that can change. They also appear in equations, which can be solved to find the value of the variable, or in formulas, which describe relationships between variables.

The most commonly used variables are and , however any letter or symbol can be used. In GCSE maths and are often used as general unknowns in equations, or as coordinates in geometry. and are usually used to represent coefficients in quadratic equations, and are also regularly seen to represent angles in geometric problems. and often represent unknown probabilities and typically stands for the radius of a circle. You may also have seen times when a star (*) or blank box (□) have been used to represent a number that needs to be found.

In GCSE maths, a variable can either represent a single value or a range of possible values. For example, in the equation , is the only possible value for . However in the equation , the variable can take on any value and the value of will change depending on the value of .

Variables revision resources to ace your exams

You can find out more about variables, and how they can be used, by reading our revision notes. To test your knowledge, try our exam questions in the algebra section.

For quick-fire GCSE maths revision, use our collection of interactive flashcards for GCSE maths. We also have past papers for your exam practice.

Explore our GCSE maths revision resources