SOLUTION: Please help me find the vertice and foci for this ellipse: {{{x^2+9y^2=18}}}

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Question 584510: Please help me find the vertice and foci for this ellipse: x%5E2%2B9y%5E2=18
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
find the vertices and foci for this ellipse:
x^2+9y^2=18
divide by 18
x^2/18+y^2/2=1
This is an equation of an ellipse with horizontal major axis of the standard form:
(x-h)^2/a^2+(y-k)^2/b^2=1, a>b, (h,k) being the (x,y) coordinates of the center.
For given equation:
center(0,0)
a^2=18
a=√18≈4.24
vertices=(0±a,0)=(0±√18,0)=(0±4.24,0)=(-4.24,0) and (4.24,0)
..
b^2=2
b=√2≈1.41
..
Foci:
c^2=a^2-b^2=18-2=16
c=√16=4
Foci=(0±c,0)=(0±4,0)=(-4,0) and (4,0)