SOLUTION: log(x-30)=3-logx
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Question 629966
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log(x-30)=3-logx
Answer by
Charles3475(23)
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log(x-30)=3-logx
(make both Side Exponents of 10)
(10^(a-b) = 10^a/10^b)
(simplify 10^log(a) = a)
(multiply both sides by x)
(subtract 1000 from both sides)
(Factor quadratic)
Either (x-50) = 0 or (x+20) = 0
x = 50 or x = -20 (solve)
However, x = -20 is an invalid solution as you can's take the log of a negative number.
x = 50 (answer)