Answer
We can't further factor this trinomial.
Work Step by Step
When factoring $ax^{2}+bx+c$, we search for factors of $ac$ whose sum is $b,$
and, if we find them, we rewrite $bx$ and proceed to factor in groups.
Here, factors of $9\times(-2)=-18$ that add to $+4$ are .... we can't find such a pair.
$(-3)\times 6$ add to $+3,$
$(-2)\times 9$ add to $+7$, etc.
No two add to $4$.
We can't further factor this trinomial.