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    I know you have to get it into the formate (x-a)^2+(y-b)^2=r^2

    Then you can work out the coordinates and use Pythagorus theorem to find out the radius


    any help ?
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    You seem to know the method, what have you done so far?
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    (Original post by User32432432)
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    I know you have to get it into the formate (x-a)^2+(y-b)^2=r^2

    Then you can work out the coordinates and use Pythagorus theorem to find out the radius


    any help ?
    Do you know how to complete the square?
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    (Original post by raiden95)
    You seem to know the method, what have you done so far?
    dont really know were to start
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    (Original post by Mr M)
    Do you know how to complete the square?
    yes sir
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    (Original post by User32432432)
    dont really know were to start
    Try completing the square using all terms with y as a start
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    (Original post by User32432432)
    yes sir
    Can you complete the square on this bit?

    y^2-6y
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    (Original post by Fool In The Rain)
    If you put it in the form you mentioned, you should get:
    x^2+(y-3)^2-7=0
    That will give you your coordinates.

    Then you expand the brackets, that will help you find the radius. (I'm not 100% sure though)
    No this is wrong, give the OP a chance to try it
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    (Original post by User32432432)
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    I know you have to get it into the formate (x-a)^2+(y-b)^2=r^2

    Then you can work out the coordinates and use Pythagorus theorem to find out the radius


    any help ?
    complete square

    arrange into circle equation format

    take the square root of r^2

    write down answer

    Job done
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    (Original post by Mr M)
    Can you complete the square on this bit?

    y^2-6y
    (y-3y)^2 +9
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    (Original post by User32432432)
    (y-3y)^2 +9
    No that's very wrong.

    Before you can tackle this question you need to go away and revise completing the square.
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    x^2 + bx = 0. 



(x+b/2)^2-(b/2)^2 = 0

    Is this any help?
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    (Original post by raiden95)
    x^2 + bx = 0. 



(x+b/2)^2-(b/2)^2 = 0

    Is this any help?
    thats what I did ?
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    (x+b/2)^2-(b/2)^2 = 0
    You didn't do that.

    (x+bx/2)^2+(b/2)^2 = 0
    You did this.
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    (Original post by raiden95)
    (x+b/2)^2-(b/2)^2 = 0
    You didn't do that.

    (x+b/2)^2+(b/2)^2 = 0
    You did this.
    No he did this:

    (x+\frac{b}{2} x)^2+(\frac{b}{2})^2 = 0
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    (Original post by Mr M)
    No he did this:

    (x+\frac{b}{2} x)^2+(\frac{b}{2})^2 = 0
    Only just noticed
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    just complete the square
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    (Original post by Mr M)
    No he did this:

    (x+\frac{b}{2} x)^2+(\frac{b}{2})^2 = 0
    Sorry for the late reply, is this correct ?
    (y+3)^2+9y
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    (Original post by User32432432)
    Sorry for the late reply, is this correct ?
    (y+3)^2+9y
    This is wrong, you need to look at completing the square in your maths text book
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    (Original post by raiden95)
    This is wrong, you need to look at completing the square in your maths text book
    Can you just explain what I have done wrong ?
 
 
 
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