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Homework Help: Fractions - showing that they are equivalent

  1. Apr 4, 2012 #1
    fractions -- showing that they are equivalent

    I have the fraction:

    a = c/d * b

    And from that I want to show that:

    a = c/(c+d) * (a+b)

    At least the two equations should be equivalent if I did everything right. How do I go from first to the second?
  2. jcsd
  3. Apr 4, 2012 #2


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    Homework Helper

    Re: fraction

    its probably easier to go from the second to the first. And then you can just do those steps in reverse if you want to show how to go from the first to the second. You see what I mean? So, if you want to do it this way, then looking at the second equation, how would you try to get it in a more simple form?
  4. Apr 4, 2012 #3

    Doc Al

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    Staff: Mentor

    Re: fraction

    Try going from the second to the first. Just substitute your first expression for a and simplify.
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