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Simple question about finding A and B

  1. Jul 5, 2012 #1
    80A = 12000 - AB
    2000A = 2000 - AB

    I can find A and B right? If not I can provide more??


    Thanks :eek: !!
     
  2. jcsd
  3. Jul 5, 2012 #2
    Yes you can find out A and B !
     
  4. Jul 5, 2012 #3
    also is there any way to set up excel so that as i change the figures the answer what A and B is automatically changes?

    i'm sorry to be so bad at math - it's been like 12 years since i stuided any :eek:
     
  5. Jul 5, 2012 #4
    honestly - i am using software that runs out in like 20 hours. this is a music hobby thing - i don't suppose you can give me the answer plus also if excell will do it for me?? i know it'd be simple for everyone here.... :) :) !!


    there are online calculators but they don't seem to cope with the A*B component!!!
     
  6. Jul 5, 2012 #5

    chiro

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    Science Advisor

    Hey clemon.

    Minus the first equation from the second and collect the terms for the A's and solve for A. Then plug A into one of the equations and solve for B.
     
  7. Jul 5, 2012 #6
    they don't converge!!

    what about:

    100=A/(100-B)+C
    12000=A/(80-B)+C
    200=A(5000-B)+C



    thanks!!
     
  8. Jul 5, 2012 #7
  9. Jul 5, 2012 #8
    thanks - i'm trying to find it with excel atm. not sure if these figures even converge tbh.
     
  10. Jul 5, 2012 #9

    HallsofIvy

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    Science Advisor

    80A = 12000 - AB
    2000A = 2000 - AB

    Didn't you consider getting rid of the "AB" term by subtracting one equation from the other? 80A- 2000A= -1920A= 10000. Solve that for A and then solve either of the two equations, using that value of A, for B
     
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