Answer
$-4$
Work Step by Step
The leading coefficient of the given trinomial is 1.
Thus, it can be factored by looking for the factors of the constant term ($20$) whose sum is equal to the numerical coefficient of the middle term ($-9$).
Note that $20=-5(-4)$ and $-5+(-4)=-9$.
Thus, the given trinomial can be factored as $(x-5)(x-4)$.
Therefore the term of the second factor is $-4$.