Find the equation relating $x$ and $y$ corresponding to the parametric equations

Find an equation relating $x$ and $y$ corresponding to the parametric equations

$$x=dfrac {3t}{(1+t^3)
}\y=dfrac {6t^2}{(1+t^3)}$$
Where $t ne −1$

by eliminating the variable $t$ and expressing the relation between $x$ and $y$ in the form
$P(x,y)=0$,
where $P(x,y)$ is a polynomial in $x$ and $y$ such that the coefficient of $x^3$ is $216$.

Answer:
eqt$=0$

What is the equation?