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Log(x+3)(2x+3)+log(x+3)(x+5)=2

User Laser Hawk
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1 Answer

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log(x-3)+log(x) = 2 + log(x+2)
---------------------------
log[(x-3)x] - log(x+2) = 2
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log[(x^2-3x)/(x+2)] = 2
----
(x^2-3x)/(x+2) = 2^2
-------

x^2-3x = 4x+8
x^2 - 7x - 8 = 0
Factor:
(x-8)(x+1) = 0
Positive solution:
x = 8
User Antonio Narkevich
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