Search
Ask a question
0 0

How to solve for x

6^x=0.25^2x-1
 
x/2x-1=log(0.25)/log(6) 
 
I've got so far.

Comments

Alain,
 
Am I supposed to interpret this as
 
6x = 0.25x - 1
 
or
 
6x = 0.25(x-1)
 
It makes a big difference!
Tutors, please sign in to answer this question.

1 Answer

Alain,
 
You were on the right track with the amount of work you did but you just need to finish it. Starting with the following:
 
x/(2x-1) = Log(0.250/log(6)
 
Now evaluate and divide the logarithms on the right side and you should get:
 
x/(2x-1) = -0.7737056145   *I write down the entire value shown on the calculator*
 
Now multiply both sides by (2x-1) and you should get:
 
x = -0.7737056145(2x-1)
 
Using the Distributive Property on the right side you should get:
 
x = -1.547411229x + 0.7737056145
 
Now add +1.547411229x to both sides and you should get:
 
x + 1.547411229x = -0.7737056145
 
Now add 1x to 1.547411229 on the left side of the equation to get:
 
2.547411229x = -0.7737056145
 
Now divide both sides by 2.547411229 and you should get:
 
x = -0.3037223067 which is the value of x.
 
Like I said, you were on the right track, you just needed to evaluate the logarithms and work with their values for a little while.