SOLUTION: log x+log(4+x)=log 5

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Question 829898: log x+log(4+x)=log 5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%29%29%2Blog%28%284%2Bx%29%29=log%28%285%29%29
log%28%28x%284%2Bx%29%29%29=log%28%285%29%29
x%284%2Bx%29=5
x%5E2%2B4x-5=0
%28x%2B5%29%28x-1%29=0
Two possible solutions:
x%2B5=0
x=-5
However checking in the original equation, log%28%28-5%29%29%29 does not exist so this is not a solution.
x-1=0
x=1
log%28%281%29%29%2Blog%28%285%29%29=log%28%285%29%29
True, this is a solution.
highlight%28x=1%29