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    How do you find the equation again?

    Coordinates:
    A(5,-1)
    B(13,11)

    a.) Find the co-ords of the midpoint AB. ---> (9,5)

    b.) AB is a diameter of the circle C, find an equation for C.
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    Ah , I just did that paper!
    well since you know AB is the diameter, the centre of the circle is the midpoint of AB (9,5) . You can then put this into the equation so (x-9)^2 + (y-5)^2 = radius^2
    Find radius by finding distance between midpoint and either a or b - take your pick!
    franks x
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    (Original post by franks)
    Ah , I just did that paper!
    well since you know AB is the diameter, the centre of the circle is the midpoint of AB (9,5) . You can then put this into the equation so (x-9)^2 + (y-5)^2 = radius^2
    Find radius by finding distance between midpoint and either a or b - take your pick!
    franks x
    (x-9)² + (y-5)² = [(√208)/2]²

    Is that right?
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    Slice did you get My message?

    Newton.
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    (Original post by Newton)
    Slice did you get My message?

    Newton.
    Yup. I've just replied.
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    Um radius^2 = 4^2 + 6^2 = 52 I think !
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    (Original post by franks)
    Um radius^2 = 4^2 + 6^2 = 52 I think !
    Oh! I used the wrong co-ordinates. Used A&B again. Oops, my mistake.

    Many thanks.
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    its ok
 
 
 
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Updated: June 15, 2005
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