SOLUTION: 7^(n+3)=80

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Question 954603: 7^(n+3)=80
Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
7^(n+3)=80
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If you want to solve for n (you should say that):
(n+3)*log(7) = log(80)
n+3 = log(80)/log(7)
n = -3 + log(80)/log(7)

Answer by Edwin McCravy(20065) About Me  (Show Source):
You can put this solution on YOUR website!
7%5E%28n%2B3%29=80

Take logs of both sides

log%28%287%5E%28n%2B3%29%29%29=log%28%2880%29%29

%28n%2B3%29log%28%287%29%29=log%28%2880%29%29

Divide both sides by log(7):

n%2B3=log%28%2880%29%29%2Flog%28%287%29%29

Subtract 3 from both sides:

n=log%28%2880%29%29%2Flog%28%287%29%29-3

Get a calculator:

n=-0.7480837762

Note: you can use "ln" (natural logarithm) instead of 
"log" (common logarithm) and get the same answer.

Edwin