SOLUTION: log3 (x) + log 3 (x-2) = log 3 (8)

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Question 63486: log3 (x) + log 3 (x-2) = log 3 (8)
Answer by joyofmath(189) About Me  (Show Source):
You can put this solution on YOUR website!
log3 (x) + log 3 (x-2) = log 3 (8)
log3(x)+log3(x-2) = log3(x(x-2)) = log3(8).
So, x(x-2) = 8, or x^2-2x-8=0.
This factors into (x+2)(x-4) = 0.
So, x=-2 or x=4.
But, if x=-2 then you're trying to get the log of a negative number. That's not defined.
So, highlight%28x=4%29 is the solution.