A curve consists of all of the points $(x, y)$ in the Cartesian plane with the sum of the distances from $(x, y)$ to $(1, 0)$ and to $(−1, 0)$ is 4 A curve consists of all of the points $(x, y)$ in the Cartesian plane such that the sum of  the distances from $(x, y)$ to $(1, 0)$ and to $(−1, 0)$ is $4$. 
Find an equation for the curve  that does not employ square roots.

This should help you:

The rest will follow...
