SOLUTION: find the vertices and foci X^2/81+Y^2/25=1

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Question 708076: find the vertices and foci
X^2/81+Y^2/25=1
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
find the vertices and foci
X^2/81+Y^2/25=1
This is an equation of an ellipse with horizontal major axis.
Its standard form: %28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1, a>b, (h,k)=(x,y) coordinates of center
For given equation:
center:(0,0)
a^2=81
a=9
b^2=25
b=5
vertices: (0±a,0)=(0±9,0)=(-9,0) and (9,0)
c^2=a^2-b^2=81-25==56
c=√56≈7.5
foci: (0±c,0)=(0±7.5,0)=(-7.5,0) and (7.5,0)