SOLUTION: please help me with these three prblems by tomarrow... 1. 3^n-2=27. 2. 2^3x+5=128 3. 5^n-3=1/25

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: please help me with these three prblems by tomarrow... 1. 3^n-2=27. 2. 2^3x+5=128 3. 5^n-3=1/25      Log On


   

Question 580765: please help me with these three prblems by tomarrow... 1. 3^n-2=27.
2. 2^3x+5=128 3. 5^n-3=1/25
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1. 3^n-2=27.
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3^(n-2) = 3^3
----
n-2 = 3
n = 5
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2. 2^3x+5=128
2^(3x+5) = 2^7
3x+5 = 7
3x = 2
x = 2/3
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3. 5^n-3=1/25
5^(n-3) = 5^(-2)
n-3 = -2
n = 1
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Cheers,
Stan H.
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