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    I'm really stuck on this question, can anyone help?
    A circle has the equation x^2+y^2+8x-4y-30=0 ( so the centre is (-4,2) )

    Find the equation of the chord AB of the circle, which passes through X (0,18/7) such that AX=BX.

    You aren't given the points A or B.
    I'll be so grateful for any help.
    Thank you in advance
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    X = 7
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    (Original post by Jory)
    X = 7
    Not meant to give full answers here.
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    Use the equation to find out the radius and work from there
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    (Original post by Megan_101)
    I'm really stuck on this question, can anyone help?
    A circle has the equation x^2+y^2+8x-4y-30=0 ( so the centre is (-4,2) )

    Find the equation of the chord AB of the circle, which passes through X (0,18/7) such that AX=BX.

    You aren't given the points A or B.
    I'll be so grateful for any help.
    Thank you in advance
    Very good question
    After finding radius which I got sqrt23 strangely , find distance between centre and x
    Then using Pythagoras you can find length bx or ax same thing. Is bx (sqrt of 327)/7?

    not sure what to do at that point onwards, could easily be overcomplicating this haha
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    I think it's y=-19/14x +18/7 but I'm not sure
    I found the radius to be 6 then did 2+6 to get (-4,8) as A then found the gradient using that and the coordinates given
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    (Original post by Megan_101)
    I'm really stuck on this question, can anyone help?
    A circle has the equation x^2+y^2+8x-4y-30=0 ( so the centre is (-4,2) )

    Find the equation of the chord AB of the circle, which passes through X (0,18/7) such that AX=BX.

    You aren't given the points A or B.
    I'll be so grateful for any help.
    Thank you in advance
    Lol misread the question, read 3 instead of 30 giving me a radius of sqrt 23 which is hopelessly wrong sorry about that lol
 
 
 

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