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Algebraic fractions - EdexcelSimplifying rational expressions

Algebraic expressions in fraction form are rational. Methods of adding, subtracting, multiplying and dividing fractions plus expanding and factorising can be used to simplify rational expressions.

Part of MathsAlgebra

Simplifying rational expressions

Simplifying expressions or algebraic fractions works in the same way as simplifying normal fractions. A common must be found and divided throughout. For example, to simplify the fraction \(\frac{12}{16}\), look for a common factor between 12 and 16. This is 4 as \(4 \times 3 = 12\) and \(4 \times 4 = 16\).

Divide 4 throughout the fraction, which gives \(\frac{12 \div 4}{16 \div 4} = \frac{3}{4}\).

Example 1

Simplify \(\frac{6m^2}{3m}\).

To simplify this, look for the of \(6m^2\) and \(3m\). This is \(3m\). Take this common factor out of each part of the fraction.

This gives \(\frac{6m^2 \div 3m}{3m \div 3m} = \frac{2m}{1} = 2m\).

This fraction cannot be simplified any further so this is the final answer.

Question

Simplify \(\frac{4(p + 7)}{(p + 7)^2}\).

Question

Simplify \(\frac{(m - 7)(m + 3)}{6(m + 3)}\).