Question

How do you convert `r=-4cos(theta)` into cartesian form?

Answer 1

`x^2+y^2+4x=0`

Explanation:

To convert polar form of equation to Cartesian form, one can use `rcostheta=x` and `rsintheta=y`. From this we also get `r^2=x^2+y^2`.

Hence, `r=-4costheta` can be written as

`r^2=-4rcostheta` or

`x^2+y^2=-4x` or

`x^2+y^2+4x=0`