Results 1 to 5 of 5

Thread: Exponential Equation

  1. #1
    Newbie
    Joined
    Sep 2009
    Posts
    23

    Exponential Equation

    3^(3x+5) = 5

    Thgis is precalc review for my calc class... I think I have to take the log of both sides and then the exponent goes out front or something like that but I'm stuck.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,237
    Thanks
    33
    $\displaystyle 3^{3x+5} = 5$

    using $\displaystyle a^b= c \Rightarrow b = \log_ac$

    then

    $\displaystyle 3x+5 = \log_35$

    Can you solve it from here?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2009
    Posts
    23
    Yes, but only with a calculator and converting to decimals. I don't really have the theory down.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    16,216
    Thanks
    3702
    Quote Originally Posted by katekate View Post
    3^(3x+5) = 5

    Thgis is precalc review for my calc class... I think I have to take the log of both sides and then the exponent goes out front or something like that but I'm stuck.
    $\displaystyle \ln(3^{3x+5}) = \ln(5)$

    $\displaystyle (3x+5)\ln(3) = \ln(5)$

    $\displaystyle 3x+5 = \frac{\ln(5)}{\ln(3)}$

    can you finish now?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Sep 2009
    Posts
    23
    yeah but with decimals again if that makes a difference.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. exponential equation#2
    Posted in the Algebra Forum
    Replies: 1
    Last Post: Sep 11th 2011, 01:13 AM
  2. Exponential equation
    Posted in the Algebra Forum
    Replies: 4
    Last Post: Oct 9th 2010, 05:47 AM
  3. Exponential Equation
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: Nov 12th 2009, 11:19 AM
  4. Exponential equation
    Posted in the Algebra Forum
    Replies: 4
    Last Post: Aug 2nd 2009, 05:13 AM
  5. exponential equation
    Posted in the Algebra Forum
    Replies: 2
    Last Post: Oct 20th 2008, 11:42 AM

Search Tags


/mathhelpforum @mathhelpforum