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Homework Help: Exponential equations homework

  1. Sep 29, 2008 #1
    1. The problem statement, all variables and given/known data
    Please , can anybody help me to do these and to explan to me?
    I tried tried, but i can't do anything.

    1. 4x-1 + 4x + 4x-1=84
    2. 15 * 2x+1 + 15 * 2 x-1 =135
    3. 8x + 18= 2* 27x
    4. 3x-8*3x/2 +15=0
    5. 5x - 53-x=20

    2. Relevant equations

    At the 5th i do like this:
    5x - 53-x=5*4 /5
    5x-1-52-x=4 and i can't do more, i have just learn for exponential equations and I don't know so good , and that is the reason that i want to help me.the problem is that i want to solve,thanks

    3. The attempt at a solution
    Last edited by a moderator: Mar 7, 2013
  2. jcsd
  3. Sep 29, 2008 #2


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    Science Advisor

    Re: Please help!

    I'm glad to hear you have tried. What have you tried? We can't make suggestions if we don't know what you already know about the problems or what you already tried. Show us what you have done.

    It would also help if you told us exactly what the problems are! You give a list of equations. Are you trying to solve the equations? And please use parentheses to clarify what you mean. I would tend to interpret "4^x-1" as 4x-1. Do you mean 4^(x-1) which is 4x-1?
  4. Sep 30, 2008 #3
    Re: Please help!

    Do you know what a logarithm is?
  5. Sep 30, 2008 #4
    Re: Please help!

    muppet , i sad before , i have just learned for exponential equations , and I don't know soo good, and if you know better please help to solve these , thank you
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