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How to you solve this simple algebra?

  1. Feb 13, 2010 #1
    This isn't a homework question...just something I picked up on a finance book about dividends. Say you have something like this.

    $30.85 = X/$1.15 + X/($1.15)^2

    How do I solve for x step by step? They give me an answer of $18.98 and if I sub that # into x I get 30.85. How do I do it the other way...algebraically?

    Last edited: Feb 13, 2010
  2. jcsd
  3. Feb 13, 2010 #2


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    Welcome to PF!

    Hi EdLeafs ! Welcome to PF! :smile:

    (try using the X2 tag just above the Reply box :wink:)
    Easy … use brackets

    30.85 = X(1/1.15 + 1/1.152) … take it from there. :smile:
  4. Feb 13, 2010 #3


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    The first thing I would do is multiply both sides by 1.15 to get rid of the fractions!

    (1.15)2(30.85)2= (1.15)X+ X= 2.15X

    Now divide both sides by 2.15.

    I'm wondering what X represents that dividing by "dollars" results in "dollars"! It has units of "dollars squared"?
    Last edited by a moderator: Feb 14, 2010
  5. Feb 13, 2010 #4


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    (erm)2 :redface:
  6. Feb 13, 2010 #5
    Ahh...I see. thanks a lot.
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