$$\left. \begin{array} { l } { \quad 1 / ( 5 x ^ { 2 } + 25 x - 9 ) - 5 ( x ^ { 2 } + 7 x - 3 ) } \end{array} \right.$$
$\frac{-25x^{4}-300x^{3}-755x^{2}+690x-134}{5x^{2}+25x-9}$
