SOLUTION: Log3(x+18)-log3(x-2)=4

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Question 1058224: Log3(x+18)-log3(x-2)=4
Found 2 solutions by Boreal, LinnW:
Answer by Boreal(15235) (Show Source):
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That is log 3 [(x+18)/(x-2)]=4
raise everything to 3rd power
(x+18)/(x-2)=81
x+18=81x-162
180=80x
x=2.25 ANSWER
log 3(20.25) is log 10 20.25/log 10 3=2.738
log 0.25 is log 10 (0.25)/ log 10 (3)=-1.261, which is subtracted, making it positive and the result 4.

Answer by LinnW(1048) (Show Source):
You can put this solution on YOUR website!
Log3(x+18)-log3(x-2)=4
Log3((x+18)/(x-2))=4
Since 4 = log3(3^4) = log3(81)
Log3((x+18)/(x-2))=log3(81)

using cross products
x+18 = 81(x-2)
x+18 = 81x -162
add -x to each side
18 = 80x -162
add 162 to each side
180 = 80x
divide each side by 80
180/80 = x
18/8 = x
9/4 = x