Algebra

Expression

A combination of numbers, letters and operations with no equals sign, e.g. 3x + 5.

Definition

An expression cannot be "solved" — it has no equation to balance. It can be simplified, expanded, factorised or substituted into.

Example

4x² − 7y + 3 is an expression. 4x² − 7y + 3 = 0 is an equation.

Common confusion

Students often try to "solve" an expression — but there is nothing to solve.

Used in these topics

Related terms

Equation

A mathematical statement with an equals sign — true for some specific value(s) of the unknown.

Identity

A statement that is true for every value of the variable. Uses the ≡ symbol.

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