SOLUTION: The ellipse with one focus at (2,5) and minor vertices at (-1,7) and (-1,3) Graph the conic and find its equation in standard form

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Question 870212: The ellipse with one focus at (2,5) and minor vertices at (-1,7) and (-1,3)
Graph the conic and find its equation in standard form

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The midpoint of the minor vertices will be the center of the ellipse. Knowing this lets you also determine the other focus.

%287%2B3%29%2F2=5, so the center of the ellipse is (-1,5).

If one focus is (2,5), then the other focus is on the other side of (-1,5), and is |-1-2|=3 units away. Starting at (-1,5), moving to the left by 3 units puts the focus at (-4,5). No matter. The focal length is c=3.

Looking at minor vertices, distance from 7 to 3 is 4; half of this is 4%2F2=2. This means, b=2.

a%5E2%2Bb%5E2=c%5E2
a%5E2=c%5E2-b%5E2
a%5E2=3%5E2-2%5E2=5

EQUATION: highlight%28%28x%2B1%29%5E2%2F5%2B%28y-5%29%5E2%2F4=1%29