find h in the ellipse if

where a, b are the axes of the ellipse.

Printable View

- Jul 22nd 2011, 03:02 AMrazemsoft21Equation of an ellipse.
find h in the ellipse if

where a, b are the axes of the ellipse. - Jul 22nd 2011, 04:58 AMmr fantasticRe: Equation of an ellipse.
- Jul 22nd 2011, 05:24 AMSironRe: Equation of an ellipse.
I agree with mr.fantastic, but let then you have a hyperbola. You know the equation of a hyperbola in general:

Now, for :

Consider the given equation:

(because h>0, we may divide the sides by h and also -h)

Now we have the standard equation of the hyperbola and that means you can determine and . - Jul 22nd 2011, 03:23 PMmr fantasticRe: Equation of an ellipse.
I had assumed as much. And I suppose the OP giving Thanks is implicit confirmation of what the correct question was meant to be.

However, I was hoping that the OP would explicitly state the correction to his/her original question (which was the intention of my post). - Jul 23rd 2011, 05:28 AMHallsofIvyRe: Equation of an ellipse.
If the "-" was simply 'misplaced' and the equation was , then we can rewrite it as

and, dividing by h, which, for h> 0,**is**an ellipse. Assuming that "a" is the length of the semi-axis along the x-axis and "b" the length of the sem-axis along the y-axis, we have and .

From the first equation and from the second . so .