The questions asks what the ( ? ) should be in: $$45x^2+26x-8=(5x+4)(?)$$ To solve for the ( ? ), we need to perform the following: $$\left(\begin{array}{cc}5& 4\\ \frac{45}{5}& \frac{-8}{4}\end{array}\right)\Rightarrow \left(\begin{array}{cc}5& 4\\ 9& -2\end{array}\right)$$ $$\Rightarrow (?)=(9x-2)$$