Answer
$(j-7)(j-6)$.
Work Step by Step
The given polynomial is
$=j^2-13j+42$
Standard form is $x^2+bx+c$.
We have $b=-13$ and $c=42$.
$b$ is negative and $c$ is positive.
Factor pair of $42$, whose sum is $-13$:-
$-7,-6$
The values of $p$ and $q$ are $-7$ and $-6$.
Hence, the factor of the polynomial is $(j+p)(j+q)=(j-7)(j-6)$.
Check:-
$=(j-7)(j-6)$
$=j^2-6j-7j+42$
$=j^2-13j+42$
True.
