Answer
$\dfrac{4}{9}$
Work Step by Step
RECALL:
$(g/f)(x)=\dfrac{g(x)}{f(x)}$
Thus,
$(g/f)(x) = \dfrac{x^2-5}{-2x+3}$
To evaluate the given expression, substitute $-3$ to $x$ in the equation above to obtain:
$g(-3)/f(-3)
\\= (g/f)(-3)
\\=\dfrac{(-3)^2-5}{-2(-3)+3}
\\=\dfrac{9-5}{6+3}
\\=\dfrac{4}{9}$