Answer
.5
Work Step by Step
We know that in the expression $log_b(a)=c$, b is the base of the exponential equation, a is what the exponential equation is equal to, and c is the exponent itself. Knowing this, we find:
$$25^x=5 \\ x=.5$$
This is because:
$$ \sqrt{25} = 25 ^ .5 $$