SOLUTION: determine the equation of the hyperbola whose vertices are the foci of the ellipse 11x^2 + 7y^2 + 14y - 70 = 0 and its foci are the vertices of the given ellipse. thanks :D

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: determine the equation of the hyperbola whose vertices are the foci of the ellipse 11x^2 + 7y^2 + 14y - 70 = 0 and its foci are the vertices of the given ellipse. thanks :D      Log On


   



Question 826098: determine the equation of the hyperbola whose vertices are the foci of the ellipse 11x^2 + 7y^2 + 14y - 70 = 0 and its foci are the vertices of the given ellipse.


thanks :D

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
determine the equation of the hyperbola whose vertices are the foci of the ellipse 11x^2 + 7y^2 + 14y - 70 = 0 and its foci are the vertices of the given ellipse.
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11x^2 + 7y^2 + 14y - 70 = 0
complete the square:
11x^2+7(y^2+2y+1)=70+7=77
x%5E2%2F7%2B%28y%2B1%29%5E2%2F11=1
This is an equation of an ellipse with vertical major axis.
Its standard form: %28x-h%29%5E2%2Fb%5E2%2B%28y-k%29%5E2%2Fa%5E2=1, a>b, (h,k)=(x,y) coordinates of center
For given equation of th ellipse:
center:(0,-1)
a^2=11
a=√11≈3.32
vertices: (0,-1±a)=(0,-1±√11)=(0,-1±3.32)=(0,-4.32)and(=(0,+2.32)
b^2=7
b=√7
c^2=a^2-b^2=11-7=4
c=±2
foci:(0,-1±c)=(0,-1±2)=(0,-3)and(=(0,+1)
..
For given hyperbola:
assume same center as given ellipse: (0,-1)
Hyperbola has a vertical transverse axis:
Its standard form of equation: %28y-k%29%5E2%2Fa%5E2-%28x-h%29%5E2%2Fb%5E2=1
a=2(foci of ellipse)
a^2=4
c^2=11(vertex of ellipse)
c^2=a^2+b^2
b^2=c^2-a^2=11-4=7
Equation of given hyperbola:
%28y%2B1%29%5E2%2F4-x%5E2%2F7=1