Finding the equation of an ellipse

Geometric formulae, word problems, theorems and proofs, etc.
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Finding the equation of an ellipse

Postby dorislouise » Wed Dec 09, 2009 4:07 pm

Find the equation of an ellipse given vertices (0, 4) and (0, -4) and which passes through the point (-1,3)

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Postby stapel_eliz » Wed Dec 09, 2009 8:00 pm

You are given the vertices of the ellipse, which are eight units apart on the y-axis, and centered on the origin. So you know that, in the ellipse equation:

. . . . .

...the value of "a" is 4, and (h, k) = (0, 0). You are given a point on the ellipse. Plug the x- and y-values from this point into the equation, along with the other known values, and solve for the one remaining value. :wink:

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