第2045题：linear equations

If the system of linear equations 

$\begin{cases} x+ky+3z=0 \\ 3x+ky-2z=0 \\ 2x+4y-3z=0 \end{cases}$

has a non-zero slution $(x,y,z)$ , then $\dfrac{xz}{y^2}$ is (   ).