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    how do i do this ive been trying for so long

    the parabola has equation y^2 = 24x
    with a focus of (6,0)
    and a directrix of x + 6 =0

    points q and p are both on the parabola and are 9 units away from the directrix of the parabola

    find the exact length of pq stating your answer as a surd

    ive ended up somehow with a triangle but have no idea what to do
    help would be really appreciated
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    (Original post by jumblebumble)
    how do i do this ive been trying for so long

    the parabola has equation y^2 = 24x
    with a focus of (6,0)
    and a directrix of x + 6 =0

    points q and p are both 9 units away from the directrix of the parabola

    find the exact length of pq stating your answer as a surd

    ive ended up somehow with a triangle but have no idea what to do
    help would be really appreciated
    are p and q on the parabola?
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    (Original post by Pheylan)
    are p and q on the parabola?
    sorry, yes,
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    (Original post by jumblebumble)
    how do i do this ive been trying for so long

    the parabola has equation y^2 = 24x
    with a focus of (6,0)
    and a directrix of x + 6 =0

    points q and p are both on the parabola and are 9 units away from the directrix of the parabola

    find the exact length of pq stating your answer as a surd

    ive ended up somehow with a triangle but have no idea what to do
    help would be really appreciated


    draw the parabola sketch and the directrix to see this
    the x values of p and q are gona be 3 since they are 9 units away from the line x=-6
    so u simply plug in x=3 in the equatiion y^2=24x to get (+/- 6root2) those are the two y values
    so the distance is gona be 2 x 6root2 which is 12root2
    hope u get it now
    the sketch should help u understand
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    (Original post by jumblebumble)
    sorry, yes,
    if the answer is 12\sqrt 2 i can help you
 
 
 
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