SOLUTION: Solve for x using natural logs: (e^2x)-(4e^x)-5=0

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Question 505457: Solve for x using natural logs:
(e^2x)-(4e^x)-5=0
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x using natural logs:
(e^2x)-(4e^x)-5=0
**
(e^2x)-(4e^x)-5=0
let u=e^x
u^2=e^2x
..
u^2-4u-5=0
(u-5)(u+1)=0
u=5
or
u=-1 (reject, e^x>0)
..
e^x=5
xlne=ln5
x=1.6094