SOLUTION: Solve for x. log3 (x+4) - log3 (x-4) = 1 Check the validity of each solution in the original equation.

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Question 437730: Solve for x.
log3 (x+4) - log3 (x-4) = 1
Check the validity of each solution in the original equation.
Found 2 solutions by stanbon, Gogonati:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x.
log3 (x+4) - log3 (x-4) = 1
----------
log3[(x+4)/(x-4)] = 1
----
(x+4)/(x-4) = 3
---
x+4 = 3x-12
2x = 16
x = 8
================
cheers,
Stan H.

Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
log%283%2C+%28x%2B4%29%29-log%283%2C+%28x-4%29%29%29=+1+, apply logarithmic properties write:
log%283%2C+%28x%2B4%29%2F%28x-4%29%29=log%283%2C+3%29%2C+because+%7B%7B%7Blog%283%2C+3%29=1
%28x%2B4%29%2F%28x-4%29=3, because we have log. with the same base on both sides.
Assume x-4 different from zero or x different from 4, multiply both sides by x-4
x+4=3(x-4) solving this equation find x=8, which is the solution.
Done.