Question

question
factor.
$x^2 + 3x - 18$

Explanation:

Step1: Find pair of factors of -18

We need two numbers that multiply to $-18$ and add to $3$. These numbers are $6$ and $-3$, since $6 \times (-3) = -18$ and $6 + (-3) = 3$.

Step2: Split middle term and factor

Rewrite the quadratic using the pair, then factor by grouping:

$$\begin{align*} x^2 + 3x - 18 &= x^2 + 6x - 3x - 18 \\ &= x(x + 6) - 3(x + 6) \\ &= (x + 6)(x - 3) \end{align*}$$

Answer:

$(x + 6)(x - 3)$