SOLUTION: Log base 2/5 X=-3

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Question 739516: Log base 2/5 X=-3
Answer by Edwin McCravy(20065) About Me  (Show Source):
You can put this solution on YOUR website!
Be sure to learn the logarithm equation 
to exponential equation principle:

The logarithm equation 

log%28B%2C%28A%29%29%22%22=%22%22C 

is equivalent to the exponential equation

A%22%22=%22%22B%5EC

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Therefore the logarithm equalion



is equivalent to the exponential equation

x%22%22=%22%22%282%2F5%29%5E%28-3%29

Invert the fraction and change the sign of the exponent:

x%22%22=%22%22%285%2F2%29%5E3

x%22%22=%22%225%5E3%2F2%5E3

x%22%22=%22%22125%2F8, or 15.625

Edwin