SOLUTION: How to find the equation of the conic with center at (-4,1), one focus at (-1,1) and corresponding directrix at x=13/4?

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Question 851968: How to find the equation of the conic with center at (-4,1), one focus at (-1,1) and corresponding directrix at x=13/4?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
How to find the equation of the conic with center at (-4,1), one focus at (-1,1) and corresponding directrix at x=13/4?
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This conic is an ellipse with horizontal major axis with center at (-4,1)
Its standard form of equation: %28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1, a>b, (h,k)=center
c=3 (distance from center to foci on the major axis)
directrix at x=13%2F4=a%2Fe=a%2F%28c%2Fa%29=a%5E2%2Fc
a^2=13c/4=39/4
b^2=a^2-c^2=39/4-9=39/4-36/4=3/4
equation:
%28x%2B4%29%5E2%2F%2839%2F4%29%2B%28y-1%29%5E2%2F%283%2F4%29=1