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Math Help - Find an equation of the parabola that has a focus at

  1. #1
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    Find an equation of the parabola that has a focus at

    Focus at (9,7) and vertex at (9,3)

    y=??



    also find equiaton of directx

    y=??
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  2. #2
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    (x-x_0)^2=4a(y-y_0) where (x_0,y_0) is the vertex of the parabola. You can see from a figure that a=7-3=4. Therefor the equation of the parabola is: y=\frac {x^2-18x+129}{16}. The equation of the directrix is: y=3-4=-1.
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  3. #3
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    Quote Originally Posted by tiga killa View Post
    Focus at (9,7) and vertex at (9,3)

    y=??



    also find equiaton of directx

    y=??
    Hi tiga killa,

    See diagram.
    Attached Thumbnails Attached Thumbnails Find an equation of the parabola that has a focus at-parabola.jpg  
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