SOLUTION: how do i find center and foci of (x^2)/9 + (y^2)/12 = 1? Is the center (0,0)?

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Question 971572: how do i find center and foci of (x^2)/9 + (y^2)/12 = 1?
Is the center (0,0)?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
a%5E2=12 and b%5E2=9; and there is a number c, the distance from center to either focus. Studying the derivation of equation for an ellipse, a relationship b%5E2=a%5E2-c%5E2 occurs.

Your center point (h,k) should be apparent directly from your given equation. YES! The origin is the center.

Now, compute the value for c. Use it to find the foci.
9=12-c%5E2
9-12=-c%5E2
12-9=c%5E2
c%5E2=3
c=0%2B-+sqrt%283%29