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| Question 410543:  I am trying to figure out how to find the value of x.
 1/25=5^(x+4)
 Answer by Theo(13342)
      (Show Source): 
You can put this solution on YOUR website! your equation is: 
 1/25 = 5^(x+4)
 
 take the log of both sides of this equation to get:
 
 log(1/25) = log(5^(x+4))
 
 since log (a^b) =b*log(a), then if you let 5 = a and you let (x+4) = b, then you get:
 
 log(1/25) = (x+4)*log(5)
 
 divide both sides of this equation by log(5) to get:
 
 x+4 = log(1/25) / log(5)
 
 subtract 4 from both sides of this equation to get:
 
 x = log(1/25) / log(5) - 4
 
 solve by using your calculator to get:
 
 x = -6
 
 your answer should be x = -6
 
 when x = -6, the equation of:
 
 1/25 = 5^(x+4) becomes:
 
 1/25 = 5^(-6+4) which becomes:
 
 1/25 = 5^(-2) which becomes:
 
 1/25 = 1/5^2 which becomes:
 
 1/25 = 1/25
 
 this confirms the answer is correct.
 
 the answer is x = -6.
 
 
 
 
 
 
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