Answer
$(n-4)(n-7)$
Work Step by Step
The following pairs of numbers give a product of $
28
:$
\begin{array}{l}\require{cancel}
\{ 1,28 \}
\text{ }
\{ -1,-28 \}
\text{ }
\{ 2,14 \}
\text{ }
\{ -2,-14 \}
\text{ }
\{ 4,7 \}
\text{ }
\{ -4,-7 \}
.\end{array}
Of these pairs, the one which gives a sum of $
-11
$ is the pair $\{
-4,-7
\}.$
Hence, the factored form of the given expression, $
n^2-11n+28
$ is
\begin{array}{l}\require{cancel}
(n-4)(n-7)
.\end{array}
