a. \(\dfrac{5}{x}=\dfrac{-3}{9}\)
\(\Rightarrow x.\left(-3\right)=5.9\)
\(x.\left(-3\right)=45\Rightarrow x=-15\)
b. \(\dfrac{x}{-8}=\dfrac{3}{-6}\)
\(\Rightarrow x.\left(-6\right)=\left(-8\right).3\)
\(x.\left(-6\right)=-24\Rightarrow x=4\)
c. \(\dfrac{x}{-7}=\dfrac{-4}{-14}\)
\(\Rightarrow x.\left(-14\right)=\left(-7\right).\left(-4\right)\)
\(x.\left(-14\right)=28\Rightarrow x=-2\)