Finding the equation of an ellipse

Hello,

I have an assigned question which asks:

In the x-y plane let L be the line x = 1, let the point O be the origin,

and set L = 1

Find an equation for the set of points P = (x, y) such that the

ratio of the distances |OP|/|PM|= 1/2 where M is the point on

the line L that is closest to P. Note that from the class lecture on

the Kepler problem, you know that this curve is an ellipse. Since

one of the foci of the ellipse is at the origin, the equation may

not look like what you are used to.

Our lecture did not cover how to find the equation of the ellipse however if briefly described it and I have been looking in my text book for help but with no luck. If anyone could give me any advice and help me out I would really appreciate it.

Re: Finding the equation of an ellipse

Re: Finding the equation of an ellipse

Thanks so much, this was a huge help.