SOLUTION: Solve for X. (Type an integer or simplified fraction). log x+log (x-15)=2

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Question 277669: Solve for X. (Type an integer or simplified fraction).
log x+log (x-15)=2
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for X. (Type an integer or simplified fraction).
log x+log (x-15)=2
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log(x(x-15)) = 2
x(x-15) = 10^2
x^2-15x - 100 = 0
(x-20)(x+5) = 0
Positive solution:
x = 20
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Cheers,
Stan H.