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I have this model: enter image description here

What values do I have:

1) $D_M$

2) $D_L - D_R$

What I can't figure out, is how to calculate the $C$ position represented on this image.

I don't have $D_L$ and $D_R$ individually, just the difference of them.

If you could help with some reference on how I can calculate the $C$ position, I would be grateful.

Thanks in advance.

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up vote 3 down vote accepted

You can't determine $C$ just from the difference. There's an entire one-dimensional curve of points that have the same difference of distances; in fact, this is one of the definitions of a hyperbola.

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P.S.: "one-dimensional" referred to the problem in the plane. If you're doing this in space, there's in fact an entire surface, a hyperboloid (of revolution), with the same difference of distances. – joriki May 27 '11 at 3:30

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