Hi All

Can anyone help me with regards ellipse geometry.

I have an issue were i have to be able to calculate the major and minor axis of an ellipse when i have the circumference.

I know Ellipse Circumference = pi*sqrt((major^2+minor^2)/2)

My relation from major to minor is: major = minor + constant (say 2.5 to start)

This now leaves me with:

Ellipse Circumference = pi*sqrt(((minor + 2.5)^2+minor^2)/2)

I have re-arranged the equation to give me:

2*((ellipse circumference/pi)^2) = (minor + 2.5)^2 + minor^2

Continuing to manipulate I get:

2*((ellipse circumference/pi)^2) = 2*minor^2 + 5*minor + 6.25

I am now stuck on where to go to calculate minor if i know the circumference as using a quadratic equation -b (+/-) sqrt(b^2-4ac)/2a I am left with a negative square root which i can not solve.

Can anyone HELP, where do i go from here?