SOLUTION: solve the equation 5/1+2e^-x = 4 please help me solve the equation

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Question 197296: solve the equation
5/1+2e^-x = 4
please help me solve the equation
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
5%2F%281%2B2e%5E%28-x%29%29=4 Start with the given equation


5=4%281%2B2e%5E%28-x%29%29 Multiply both sides by 1%2B2e%5E%28-x%29


5=4%2B8e%5E%28-x%29 Distribute


5-4=8e%5E%28-x%29 Subtract 4 from both sides


1=8e%5E%28-x%29 Combine like terms.


1%2F8=e%5E%28-x%29 Divide both sides by 8


1%2F8=1%2Fe%5Ex Rewrite e%5E%28-x%29 as 1%2Fe%5Ex


e%5Ex=8 Cross multiply


x=ln%288%29 Take the natural log of both sides (to eliminate the base "e" and isolate "x")



So the solution is x=ln%288%29 which approximates to

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the equation
5/1+2e^-x = 4
------------------
5/[1+2e^(-x)] = 4
[1+2e^(-x)] = 5/4
2e^(-x) = 1/4
e^(-x) = 1/8
-x = ln[1/8]
-x = -2.0794
x = 2.0794
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Cheers,
Stan H.