Answer :
[tex]3z=y\\
z=\dfrac{y}{3}\\\\
3x=2\cdot\dfrac{y}{3}\\
x=\dfrac{2y}{9}[/tex]
[tex]2z=3x\ \ \ |divide\ both\ sides\ by\ 2\\\\z=1.5x\\\\subtitute\ to\ 3z=y\\\\3(1.5x)=y\\\\4.5x=y\ \ \ \ |multiply\ both\ sides\ by\ 2\\\\9x=2y\ \ \ \ |divide\ both\ sides\ by\ 9\\\\\boxed{x=\frac{2}{9}y}[/tex]