SOLUTION: how do u solve 2 log3 (x+4)- log3 9=2

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Question 184651This question is from textbook
: how do u solve 2 log3 (x+4)- log3 9=2 This question is from textbook

Found 2 solutions by stanbon, kdepasquo137:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve 2 log3 (x+4)- log3 9=2
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log3 (x+4)^2 - log3 9 = 2
log3 (x+4)^2 - 2 = 2
log3 (x+4)^2 = 0
(x+4)^2 = 3*0
(x+4)^2 - 1 = 0
x^2 + 8x + 15 = 0
(x+5)(x+3) = 0
x= -5 or x = -3
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Both of these are extraneous solutions as you would find
out if your substituted them in the original equation.
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Cheers,
Stan H.

Answer by kdepasquo137(1) About Me  (Show Source):
You can put this solution on YOUR website!
2 log3 (x+4) - log3 9 = 2
2 log3 (x+4) - 2 = 2
2 log3 (x+4) = 4
log3 (x+4)= 2
x+4 = 3^2
x+4 = 9
x = 5