# Changing parametric equation to cartesian

• May 23rd 2010, 10:43 PM
arze
Changing parametric equation to cartesian
I've got this parametric equations:
$x=\frac{c(t^4+1)}{2t^3}$
$y=\frac{c(t^4+1)}{2t}$
t is the variable
I am supposed to find the Cartesian equation of these points, are there any pointers like things to look out for when trying to convert such things? I want to try it myself, but i need some guidance as to where to start when dealing with such equations.
Thanks!
• May 23rd 2010, 10:58 PM
Hello arze
Quote:

Originally Posted by arze
I've got this parametric equations:
$x=\frac{c(t^4+1)}{2t^3}$
$y=\frac{c(t^4+1)}{2t}$
t is the variable
I am supposed to find the Cartesian equation of these points, are there any pointers like things to look out for when trying to convert such things? I want to try it myself, but i need some guidance as to where to start when dealing with such equations.
Thanks!

It's difficult to define any hard-and-fast rules. Obviously, you have to eliminate $t$ between the two equations, so you'll have to look for ways to do this. You could try to isolate $t$ and then eliminate it by substitution.

In this case, the equations only differ in the power of $t$ in the denominators on the right-hand-sides. So
$y = t^2x$
Now make $t$ the subject of this equation, and eliminate it by substituting into whichever of the original equations looks like being the easier.