SOLUTION: what is the equation for this ellipse with a foci at (1,-4) and (-3,-4) and a length major axis at 12?

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Question 673090: what is the equation for this ellipse with a foci at (1,-4) and (-3,-4) and a length major axis at 12?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
what is the equation for this ellipse with a foci at (1,-4) and (-3,-4) and a length major axis at 12?
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Foci information show this is an ellipse with horizontal major axis.
Its standard form of equation: %28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1, a>b, (h,k)=(x,y) coordinates of center.
For given ellipse:
center: (-1,-4) (midpoint of x-coordinate and y-coordinate of foci)
given length of major axis=12=2a
a=6
a^2=36
c=2 (distance from center to foci on horizontal major axis)
c^2=4
c^2=a^2-b^2
b^2=a^2-c^2=36-4=32
Equation of given ellipse:
%28x%2B1%29%5E2%2F36%2B%28y%2B4%29%5E2%2F32=1