Example

Solve for :

Solution

We should always start by trying to factor. If the quadratic expression on the left does factor nicely, then we could find two integers whose product is and whose sum is . There are no such integers, so we give up on factoring. Let's go right to the quadratic formula.

In this problem, we have

It follows that

or

There are two solutions,

and these can be simplified by canceling a factor of . After doing so, we have