## Elementary Algebra

$(x+2)(x+7)$
The following pairs of numbers give a product of $14 :$ \begin{array}{l}\require{cancel} \{ 1,14 \} \text{ } \{ 2,7 \} .\end{array} Of these pairs, the pair $\{ 2,7 \}$ gives a sum of $9 .$ Hence, the factored form of the given expression, $x^2+9x+14$ is \begin{array}{l}\require{cancel} (x+2)(x+7) .\end{array}