Answer
not factorable with integer coefficients
Work Step by Step
$\bf{\text{Solution Outline:}}$
To factor the quadratic expression $x^2+bx+c,$ find two numbers, $m_1$ and $m_2,$ whose product is $c$ and whose sum is $b$. Then, express the factored form as $(x+m_1)(x+m_2).$
$\bf{\text{Solution Details:}}$
In the given expression, $
p^2q^2-5pq-18
,$ the value of $c$ is $
-18
$ and the value of $b$ is $
-5
.$
The possible pairs of integers whose product is $c$ are
\begin{array}{l}\require{cancel}
\{1,-18\}, \{2,-9\}, \{3,-6\},
\{-1,18\}, \{-2,9\}, \{-3,6\}
.\end{array}
Among these pairs, none gives a sum of $b.$ Hence, the given expression is $\text{
not factorable with integer coefficients
.}$