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Math Help - Conic Sections

  1. #1
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    Conic Sections

    Hi guys.

    So I need help with this problem.

    This is supposedly a conic
    9(x-2)^2 +5(y-2)^2=-36-30y+82

    I simplified it and got
    9x^2 +5y^2-1=0

    This is the form Ax^2 +Cy^2+Dx+Ey+F=0
    I'm guessing this is an ellipse, but how do i convert this to the standard ellipse form (x^2/a^2+y^2/b^2=1)

    If someone could help me, that would be great. I am seriously lost.

    Thanks!
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  2. #2
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    Re: Conic Sections

    Quote Originally Posted by pixel765 View Post
    This is supposedly a conic
    9(x-2)^2 +5(y-2)^2=-36-30y+82

    I simplified it and got
    9x^2 +5y^2-1=0

    Thanks!
    When I simplified it I got

    9x^2+5y^2-36x+10y+10=0

    (I could have made a mistake but I don't think that I did)

    and I think that this is what it looks like
    b3e3bb9fc36b4700dc41c65050ef9918.gif
    Last edited by Melody2; December 1st 2013 at 05:14 PM.
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  3. #3
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    Re: Conic Sections

    Quote Originally Posted by pixel765 View Post
    This is supposedly a conic
    9(x-2)^2 +5(y-2)^2=-36-30y+82
    I simplified it and got
    9x^2 +5y^2-1=0
    Warning: I did not check your algebra.

    But 9x^2 +5y^2=1 is an ellipse.
    In standard form it is: \frac{x^2}{9^{-1}}+\frac{y^2}{5^{-1}}=1
    You can see that the center is (0,0) and the major-axis is vertical.
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  4. #4
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    Re: Conic Sections

    Quote Originally Posted by pixel765 View Post
    Hi guys.


    This is supposedly a conic
    9(x-2)^2 +5(y-2)^2=-36-30y+82

    I simplified it and got
    9x^2 +5y^2-1=0


    Thanks!
    So, did you want the first ellipse or the second one.
    If it is my error I will be seriously embarassed.
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