SOLUTION: What are the foci for the equation 27x^2+9y^2=81

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Question 817900: What are the foci for the equation 27x^2+9y^2=81
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

27x^2+9y^2=81

x%5E2%2F3+%2B+y%5E2%2F9+=+1 C(0,0) a = 3  and b = sqrt(3)

± sqrt(9-3) = ± sqrt(6)  F(0,sqrt%286%29) and (0,  -sqrt%286%29)

Standard Form of an Equation of an Ellipse is %28x-h%29%5E2%2Fa%5E2+%2B+%28y-k%29%5E2%2Fb%5E2+=+1+ 

where Pt(h,k) is the center. (a variable positioned to correspond with green%28major+axis%29

 a and b  are the respective vertices distances from center

 and ±sqrt%28a%5E2-b%5E2%29are the foci distances from center: a > b