Answer
$\dfrac{-7\sqrt{x}-21}{x-9}$
Work Step by Step
Rationalizing the denominator of $
\dfrac{-7}{\sqrt{x}-3}
$ results to
\begin{array}{l}
\dfrac{-7}{\sqrt{x}-3}
\cdot
\dfrac{\sqrt{x}+3}{\sqrt{x}+3}
\\\\=
\dfrac{-7\sqrt{x}-21}{(\sqrt{x})^2-(3)^2}
\\\\=
\dfrac{-7\sqrt{x}-21}{x-9}
.\end{array}