Substitution

Replace letters with specific numbers and calculate the resulting value.

What you'll learn

Core 11+ exam skills

Basic Substitution

Develop foundational techniques logically.

Negative Substitution

Apply mathematical rules to varying scenarios.

Using Formulae

Learn to track calculations dynamically.

Evaluating Expressions

Verify accuracy and solve efficiently.

The mechanics of Substitution

Replacing Variables

Swap the letter for its known value in brackets.

Using BODMAS

Apply normal order of operations after substituting.

Negative Values

Be careful substituting negatives into squares.

Scientific Formulae

E.g., v = u + at.

💡

Always substitute negative numbers inside brackets: (-3)²

🔄

If x=2, then 3x means 3 × 2 = 6 (not 32!).

➕

Substitution is heavily used in physics and computing.

➖

Check your BODMAS when calculating the final value.

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