SOLUTION: log3(y-2)+log3y=4

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Question 429482: log3(y-2)+log3y=4
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Solution:log%283%2C%28y-2%29%29%2Blog%283%2Cy%29=4
Express 4 as logarithm with base 3 : log%283%2Cx%29=4=> 3^4=x =>x=81.
log%283%2Cy%28y-2%29%29=log%283%2C81%29
y(y-2)=81 Set equation to zero and solve it.
y%5E2-2y-81=0
y=%282%2B-sqrt%284%2B324%29%29%2F2
The solution is 1%2Bsqrt%2882%29.Approximately 10.
Done.