Precalculus Examples

$x^{2} - 22 x + 105$

Step 1

Consider the form $x^{2} + b x + c$ . Find a pair of integers whose product is $c$ and whose sum is $b$ . In this case, whose product is $105$ and whose sum is $- 22$ .

$- 15, - 7$

Step 2

Write the factored form using these integers.

$(x - 15) (x - 7)$