Substitution
What Substitution means in Mathematics GCSE, as defined for AQA, Pearson Edexcel.
Definitions of Substitution
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Reference: AQA
Rearranging the linear equation to make one variable the subject, then substituting this expression into the quadratic equation.
Putting a given number in place of each letter, then working the expression out.
Replacing a variable with a specified numerical value while preserving the operations in the expression or equation.
Replacing a variable with a specified value and then calculating the resulting expression.
Replacing a variable with a given value and calculating the resulting expression.
Replacing a variable with an equal value or expression in another equation.
Topics that use Substitution
- Graphs (AQA GCSE)
- Solving equations and inequalities (AQA GCSE)
- Algebra - Notation, vocabulary and manipulation (Pearson Edexcel GCSE)
- Algebra - Sequences (Pearson Edexcel GCSE)
- Algebra - Solving equations and inequalities (Pearson Edexcel GCSE)
Related terms
- Coefficient
- completing the square
- collecting like terms
- constant
- Factor
- Linear equation
- monic quadratic
- quadratic equations
Using Substitution in the exam
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