SOLUTION: ln(x + 8) – ln(x – 4) = ln x

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Question 739571: ln(x + 8) – ln(x – 4) = ln x

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
ln(x + 8) – ln(x – 4) = ln x
ln[(x+8)/(x-4)]=ln(x)
(x+8)/(x-4)=x
x^2-4x=x+8
x^2-5x-8=0
solve for x by quadratic formula:
x≈-1.275(reject,(x-4)>0)
or
x≈6.275