SOLUTION: Can anyone help with this one? 3^(2x+5) = 4 I started with (2x+5) log3 = log4 then 2xlog3 + 5log3 = log4 but now I'm lost, I know the answer is -1.87

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: Can anyone help with this one? 3^(2x+5) = 4 I started with (2x+5) log3 = log4 then 2xlog3 + 5log3 = log4 but now I'm lost, I know the answer is -1.87      Log On


   

Question 20604: Can anyone help with this one?
3^(2x+5) = 4
I started with (2x+5) log3 = log4
then 2xlog3 + 5log3 = log4
but now I'm lost,
I know the answer is -1.87
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You got a good start.
3%5E%282x%2B5%29+=+4 Take the log of both sides.
%282x%2B5%29log%283%29+=+log%284%29 Divide both sides of the equation by log(3).
2x%2B5+=+%28log%284%29%29%2Flog%283%29 Subtract 5 from both sides.
2x+=+%28%28log%284%29%29%2Flog%283%29%29+-+5 Use you calculator to find %28log%284%29%29%2Flog%283%29
2x+=+1.262+-+5
2x+=+-3.738 Divide both sides by 2.
x+=+-1.869