SOLUTION: I need help graphing the ellipse and finding the foci of the following equation: 5x^2+y^2=25

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Question 174756This question is from textbook
: I need help graphing the ellipse and finding the foci of the following equation: 5x^2+y^2=25 This question is from textbook

Found 2 solutions by stanbon, Mathtut:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I need help graphing the ellipse and finding the foci of the following equation: 5x^2+y^2=25
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Divide thru by 25 to get: x^2/5 + y^2/25 = 1
a = sqrt(25)=5 ; b = sqrt(5)
Therefore c = sqrt(a^2+b^2) = sqrt(25+5) = sqrt(30)
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Center is at (0,0)
Major-axis vertices are: (0,5) and (0,-5)
Minor-axis vertices are: (sqrt(5),0) and (-sqrt(5),0)
Foci:(0,sqrt(30)) and (0,-sqrt(30))
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Cheers,
Stan H.

Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
lets get this in the right form x%5E2%2Fa%5E2%2By%5E2%2Fb%5E2=1
:
5x%5E2%2F25%2By%5E2%2F25=1
:
x%5E2%2F%28sqrt%285%29%29%5E2%2By%5E2%2F5%5E2
:
the foci are at (0,plus and minus c) where c=sqrt(a^2+b^2)
so c=sqrt%285%2B25%29=sqrt%2830%29 ..so foci are at (0,sqrt(30) and (0,-sqrt(30))
:
major axis is at (0,5) and(0-5) minor axis at (sqrt(5),0)(-sqrt(5),0)
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