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Homework Help: Idiot question on rearranging

  1. Jan 23, 2006 #1
    Could someone please write the steps in rearranging this ..I just can't get it

    mg+ma-Mg=-Ma

    becomes
    a=(M-m/M+m)g


    Sorry it's so basic
    Thanks
     
  2. jcsd
  3. Jan 23, 2006 #2
    Put terms with a on one side, terms with g on the other side. Factor out a and g. Divide one side by the coefficient on the other side.
     
  4. Jan 23, 2006 #3
    Algebra. You're trying to get a "by itself".

    One way would be to start by getting two things you can factor.

    Step one: Bring ma to the right by subtracting it from both sides, which gives: mg - Mg = -Ma - ma.

    Step two: Factor both sides: g(m - M) = a(-M - m)

    Step three: Divide: g(m - M)/(-M - m) = a

    A.K.A. = a = g(m - M)/(-M - m).

    Or at least that's how I'd do it. Not sure if that's what you have.
     
  5. Jan 23, 2006 #4
    Excellent thats cleared it up for me.
    Thanks again.
     
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