Explanation:
since sqrt(25)×sqrt(25) = 25, then x can be any number, because x = x in all cases. and then both sides of the equation are always equal, no matter what value we give x, as long as x is a factor in both sides.
sqrt(25)×x×sqrt(25) = 25x
is always true for every x.
if the question would be
sqrt(25)×x×sqrt(25) = 25
then the answer can only be x = 1. because for every other value of x the equality is destroyed.