Can you help me with the following logarithm and 
explain how you came to the answer?:

log5x = -2

You must memorize how to rewrite a log equation as an exponential
equation and vice-versa:

Rule:

The logarithm equation 

logba  = c

and the exponential equation

bc = a

are equivalent and you can always
write one for the other.  

Using that rule:

log5x = -2

can be rewritten as

5-2 = x

Then use the rule for negative exponente
to write  as  and then
write that as  .

That's the answer 

x = 



Edwin