SOLUTION: please help me solve this equation log(x) + log(x - 90) = 3

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Question 170821: please help me solve this equation log(x) + log(x - 90) = 3
Answer by KnightOwlTutor(293) About Me  (Show Source):
You can put this solution on YOUR website!
We know that the log base is 10 therefore
x(x-90)=1000
x^2-90x-1000=0
Let's factor this equation
(x-100)(x+10)=0

x=100
log 100 +log(100-90)=3
2+1=3