Answer
$(y-1)(y-12)$
Work Step by Step
Using the factoring of trinomials in the form $x^2+bx+c,$ the given expression, $
y^2-13y+12
,$ has $c=
12
$ and $b=
-13
.$
The two numbers with a product of $c$ and a sum of $b$ are $\left\{
-1,-12
\right\}.$ Using these two numbers, the factored form of the expression above is
\begin{align*}
(y-1)(y-12)
.\end{align*}
