SOLUTION: ln(x) + ln(x-7) = ln5x x=?

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Question 13567: ln(x) + ln(x-7) = ln5x
x=?
Answer by rahman(247) About Me  (Show Source):
You can put this solution on YOUR website!
ln(x) + ln(x-7) = ln(5x)
ln%28x%2A%28x-7%29%29+=+ln%285x%29
ln%28x%2Ax-x%2A7%29+=+ln%285x%29
ln%28x%5E2-7x%29+=+ln%285x%29
So:
x%5E2-7x+=+5x
x%5E2-7x-5x=+0
x%5E2-12x=+0
x%28x-12%29=+0
x=0 or x-12=0 -----> x = 12
x = 12 is solution
OK