If [tex] \left \{ {{x=3t} \atop {y= t^{2} }} \right. [/tex] then [tex]t= \frac{x}{3} [/tex] and [tex]y=( \frac{t}{3} )^2= \frac{t^{2}}{9} [/tex].
You can match points:
if x=0, y=0
if x=3, y=1
if x=-3, y=1
if x=6, y=4
if x=-6, y=4
The graph is in attached file
