IGCSE Maths / Working with algebra

Changing the subject of a formula revision notes

Edexcel International GCSE Maths (4MA1), chapter 4: Working with algebra, specification point 2.3a. Part of the full course.

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Changing the subject means rearranging a formula until the letter you want is alone on one side. Undo operations in reverse order, applying each operation to both sides and keeping brackets or roots over the whole expression.

More lessons in Working with algebra

• Order of operations
• Collecting like terms
• Substituting into expressions and formulae
• Index laws with algebraic terms
• Fractional indices
• Expanding a single bracket
• Expanding double brackets
• Expanding triple brackets
• Factorising with a common factor
• Factorising quadratics of the form x squared plus bx plus c
• Factorising with a coefficient
• Difference of two squares
• Writing and deriving a formula
• When the subject has a power on it