If $x+3y=15, \; 2x + y =9$ is a given system of equations, what can be the value of $\large\frac{x}{y}$ ?

Question

$\begin{array}{1 1} (a)\;3 \\ (b)\; -3 \\ (c)\; \frac{1}{3} \\ (d)\; \frac{-1}{3} \end{array}$