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Homework Help: How Do You Rewrite Equations

  1. Sep 18, 2008 #1
    How Do You Rewrite Equations? Can You Show All The Steps. For Say
    d=(vi+vf)/2 and your trying to get vf where the d is.

  2. jcsd
  3. Sep 18, 2008 #2


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    You need to learn properties of Real numbers. This is generally how "Algebra 1" begins. Also, in your question, are the "i" and the "f" supposed to be subscripts for your variable names, or are they variables themselves? Anyway, show you work, and USE the properties of Real numbers which you are probably right now studying .
  4. Sep 18, 2008 #3
    That Doesnt help me at all can some one help please!
  5. Sep 18, 2008 #4


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    Staff: Mentor

    To re-write equations, you do the same operation to both sides to keep the equation "equal". Like multiply both sides by the same number, or add subtract the same thing from both sides.

    So, for the first step, what could you do to both sides to get that pesky "2" out of the denominator of the right-hand side (RHS)?
  6. Sep 18, 2008 #5
    x 2 :)
  7. Sep 18, 2008 #6
    i still need a full example
  8. Sep 18, 2008 #7


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    Staff: Mentor

    Nope, not from us. As symbolipoint said, you need to do the work. That's how the PF works. We can offer suggestions and point out any errors in your work, but you do the bulk of the work. Please re-read the Rules at the link at the top of the page if you need clarification on that.

    So do the x2 step that you correctly said, and show us the equation that results. Then what do you think you need to do to get the vf on one side of the = sign all by itself? Do it and show us the answer.
  9. Sep 18, 2008 #8


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    If you actually bothered to do the "x2" to the equation and looked at the result, the rest is easy and obvious.
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