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Rearranging Equations where the term seems to cancel?

  1. Dec 6, 2015 #1
    So, on a recent maths paper I sat, there was a question where we had to make t the subject. (Disclaimer, this is not homework. I am simply curious, and cannot see how it works. Please don't Ban me) I could not do it for the life of me, because, seemingly the two ts cancel? I know this shouldn't happen, and my teacher went through it, however I've tried it every which way, and the solution still eludes me. gLYVTSL.jpg
    So I tried the following working, which my teacher suggested:
    So, I began by combining the fraction on the left, then I cross multiplied, collected all terms with t and... What? I can't seem to get any further, without cancelling, let alone getting rid of the b and R.

    Am I seriously missing a trick here? I've never really been that good with algebraic fractions.

    Also, any tips on the matter would be well received.
  2. jcsd
  3. Dec 6, 2015 #2


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    Why not factor out the t and then divide? The t's wouldn't cancel out anyway, there's no way to do that.
  4. Dec 6, 2015 #3

    Thank you! That makes so much sense and I feel really dumb now. I guess I forget sometimes that -Rt = -1*R*t and thus I can factor it out like that.
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