Question 444418: ln(45+6x)=2 ln(x+3)
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! ln(45+6x)=2 ln(x+3)
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ln(45+6x)=2 ln(x+3)
ln(45+6x)-2 ln(x+3)=0
ln(45+6x)-ln(x+3)^2=0
ln(45+6x)/(x+3)^2=0
convert to exponential form (base=e, raised to log of number=0, is =number, (45+6x)/(x+3)^2
e^0=(45+6x)/(x+3)^2=1
45+6x=(x+3)^2
45+6x=x^2+6x+9
x^2-36=0
(x+6)(x-6)=0
x=-6 (reject,(x+3)>0
or
x=6 (ans)
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