# How do you simplify (x + 7)(x - 7)?

Jul 19, 2016

${x}^{2} - 49$

#### Explanation:

There are 2 binomials to be multiplied. This can be done by usual distributive method :

$\left(x + 7\right) \left(x - 7\right)$

=${x}^{2} - 7 x + 7 x - 49 \text{ which will now simplify}$

OR we should be able to instantly recognise that these are the factors which would be obtained by factoring the difference of two squares/ (The brackets are the same except for the signs)

Either method will lead to the result of
${x}^{2} - 49$