Answer
$(x-2)(x-9)$
Work Step by Step
The following pairs of numbers give a product of $
18
:$
\begin{array}{l}\require{cancel}
\{ 1,18 \}
\text{ }
\{ -1,-18 \}
\text{ }
\{ 2,9 \}
\text{ }
\{ -2,-9 \}
\text{ }
\{ 3,6 \}
\text{ }
\{ -3,-6 \}
.\end{array}
Of these pairs, the one which gives a sum of $
-11
$ is the pair $\{
-2,-9
\}.$
Hence, the factored form of the given expression, $
x^2-11x+18
$ is
\begin{array}{l}\require{cancel}
(x-2)(x-9)
.\end{array}
