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    Hi just a quick question.

    Just got my C1 book delivered and working through it.. pretty basic stuff just 1q.

    'Show that points (7,12), (-3, -12), (14, -5) lie on a circle with centre (2, 0)'

    A (7,12)
    B (-3, -12)
    C (14, -5)

    calculated

    AB = ^2root 676
    AC = ^root 338
    BC = ^root 338

    So i understand that the coordinates plot an isosceles triangle but how does it show that the ponts lie on a circle with centre (2, 0)??

    Thanks
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    The equation for that circle is (x-2)^2+y^2=r^2, where r is currently unknown. Put the values for each point you have into that equation and they should all give the same.
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    (Original post by Cerdog)
    The equation for that circle is (x-2)^2+y^2=r^2, where r is currently unknown. Put the values for each point you have into that equation and they should all give the same.
    nice one, cheers
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    (Original post by Bleak Lemming)
    Hi just a quick question.

    Just got my C1 book delivered and working through it.. pretty basic stuff just 1q.

    'Show that points (7,12), (-3, -12), (14, -5) lie on a circle with centre (2, 0)'

    A (7,12)
    B (-3, -12)
    C (14, -5)

    calculated

    AB = ^2root 676
    AC = ^root 338
    BC = ^root 338

    So i understand that the coordinates plot an isosceles triangle but how does it show that the ponts lie on a circle with centre (2, 0)??

    Thanks
    If it's Edexcel then you don't encounter the circle equation until C2.
    However, you can show that A, B and C are all the same distance from (2,0)
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    (Original post by gdunne42)
    If it's Edexcel then you don't encounter the circle equation until C2.
    However, you can show that A, B and C are all the same distance from (2,0)
    Thanks,

    Its an OCR text book but not sitting exams, just self teaching
 
 
 
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