SOLUTION: Solve : log x + log(x - 9) = 1

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Question 724108: Solve : log x + log(x - 9) = 1
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
log x + log(x-9) = 1
log (x(x-9)) = 1
x(x-9) = 10^1
x^2-9x = 10
x^2-9x-10 = 0
(x+1)(x-10) = 0
x = {-1, 10}
Throw out the negative solution (extraneous) leaving:
x = 10