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Thread: quadratic theory

  1. #1

    Thread Starter
    Frenzied Member markman's Avatar
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    In math class I came up with a theory for an equasion like:
    ax^2 + bx + c = 0
    If thought that if b-a=c Then
    the discriminant (b^2-4ac) = (a-c)^2
    I think this always works. Please correct me if I'm wrong.

    Also,
    If b-a=c Then the solutions are
    -c and c-b

    That one I am very unsure because it only sometimes works. If you can come up for something like this, please tell me.

    -mark
    retired member. Thanks for everything

  2. #2
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    ???

    if c = b - a then (B^2 - 4*a*c) = B^2 -4*a*(b-a)

    With a little work you get B^2 - 4*a*b + 4*a^2

    This is (b - 2*a)^2

    This leads to the following.

    X = [-b + (b - 2*a) ] / 2*a
    X = [-b - (b - 2*a) ] / 2*a

    X = -1
    X = (a - b)/a

    The above is the correct result for c = (b - a)

    I do not know what you want to do next.
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