Trying to pull from memory here. You have the equations for your two ellipses. Don't you just set those two equations equal to each other & solve for possible values of x & y? I found some long winded explanations by googling on "equation for where ellipses intersect", but didn't read into the specifics.



>I want to be able to determine where two ellipses intersect when they are over layed.
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>Each ellipse is the same size - same leght - same widths. The are over-layed such that their long axis bisect and are perpendicular.
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>For "minor" widths greater than zero, the ellipses would intersect at 4 points. If the points were connected, the would form a square.
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>If both ellipses were zero width they would look like a '+' sign and would all intersect at the origin (0).
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>I know the width and lenght and origin of the concentric ellipses.
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>How can I determine the intersect points? A radian lenght (distance from origin) would be okay - or a cartesian plot would also be good (either would derive the other, right?)