You can put this solution on YOUR website! 7^n=12
n*log(7) = log(12)
n = log(12)/log(7) = ~ 1.27699
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8^n+1=3
(n+1)*log(8) = log(3)
n+1 = log(3)/log(8)
n = (log(3)/log(8)) - 1
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log 3x=2
3x = 100
x = 100/3
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4log x=4
log(x) = 1
x = 10