SOLUTION: solve for x log x +log(x-15)=2

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Question 526441: solve for x
log x +log(x-15)=2
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
log x +log(x-15)=2
log x(x-15)=2
x(x-15)=10^2
x^2-15x=100
x^2-15x-100=0
(x-20)(x+5) = 0
x = {-5, 20}
we can throw out the negative solution (extraneous) leaving:
x = 20