SOLUTION: log(3) 21 - log(3) 7 = log(3)Y what and how do you find the Y?

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Question 251778: log(3) 21 - log(3) 7 = log(3)Y
what and how do you find the Y?
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
log%283%2C%2821%29%29-log%283%2C%287%29%29=log%283%2C%28y%29%29 Start with the given equation.



log%283%2C%2821%2F7%29%29=log%283%2C%28y%29%29 Combine the logs on the left side using the identity log%28b%2C%28A%29%29-log%28b%2C%28B%29%29=log%28b%2C%28A%2FB%29%29


log%283%2C%283%29%29=log%283%2C%28y%29%29 Reduce.


3=y Since the bases of the logs are equal, the arguments (the expressions inside the logs) are equal.


So the solution is y=3

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
log(3) 21 - log(3) 7 = log(3)Y
what and how do you find the Y?
------------------------
log(3)[21/7) = log(3)y
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log(3)3 = log(3)Y
1 = log(3)Y
Convert to exponential form:
y = 3^1
y = 3
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Cheers,
Stan H.