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  1. #1
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    simple equation prob...

    103= 6/1+r +106/(1+r)^2

    r=???

    Can anyone help with this? thank you
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  2. #2
    Bar0n janvdl's Avatar
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    Quote Originally Posted by flynne8 View Post
    103= 6/1+r +106/(1+r)^2

    r=???

    Can anyone help with this? thank you
    Let's say (1 + r) = x

    Then 103 = \frac{6}{x} + \frac{106}{x^2}

    [Multiply straight through with x^2]

    103x^2 - 6x - 106 = 0

    x = 1.0440028316648209

    OR

    x = -0.9857504044803549

    ---

    1 + r = 1.0440028316648209

    OR

    1 + r = -0.9857504044803549


    You can solve for r from there.
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  3. #3
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    Then

    [Multiply straight through with ]






    Why do you multiply by?and how do do this...

    Also how do you get from



    to

    ???

    Thanks
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  4. #4
    GAMMA Mathematics
    colby2152's Avatar
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    Why do you multiply by?and how do do this...
    X squared is the common denominator. Multiply each term by x squared to simplify the equality.
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  5. #5
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    Also how do you get from



    to

    ???
    The question you have been given is far too hard for you if you don't know how to solve a quadratic.

    Janvdl applied the quadratic formula: if ax^2+bx+c=0 then x = \frac {-b\pm \sqrt {b^2-4ac}}{2a}
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