Question 712771
logs are easy if you can remember: 
the log of 100 in base 10 is 2
i.e.
{{{log( 10 , 100 )=2}}}
and we know that 10 the power 2 is 100
which translates as
{{{10^2=100}}}
we can use those facts in reverse.
in your problem
i.e.
{{{(1/4)^-2=16}}}
which translates as
{{{log( (1/4) , 16)=-2}}} 
i know it looks odd but its true!
and also in the other problem
{{{b^c=a}}}
translates as
{{{log( b , a )=c}}}