SOLUTION: Given that 3^-x=5, find the value of 3^3x? Answer=1/125. I need to see how this is broken down. I'm studying for a test and can't find an example of this problem. Thank you!

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: Given that 3^-x=5, find the value of 3^3x? Answer=1/125. I need to see how this is broken down. I'm studying for a test and can't find an example of this problem. Thank you!      Log On


   

Question 867191: Given that 3^-x=5, find the value of 3^3x? Answer=1/125.
I need to see how this is broken down. I'm studying for a test and can't find an example of this problem. Thank you!
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
1%2F3%5Ex+=+5
+1%2F5+=+3%5Ex Cubing both Sides
%281%2F5%29%5E3+=+%283%5Ex%29%5E3+=+3%5E%283x%29
1/125 = 3^(3x)