SOLUTION: solve log(2k+4)=1+logk is this statement true? Explain. log(-3)+log(-4)=log12

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Question 1043515: solve
log(2k+4)=1+logk
is this statement true? Explain.
log(-3)+log(-4)=log12
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
log(2k+4)=1+logk
log (2k+4)-log (k)=1
log [(2k+4)/(k)]=1
raise everything to the 10 power
(2k+4)/(k)=10
2k+4=10k
8k=4
k=(1/2)
substitute in.
log (5)=1+log (1/2)
log (5)=1-log(2)
log (5)+log (2)=1
log (10)=1, and that is true.
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the second is not true. log (-3) does not exist.