Steve M. answered 07/11/19
Algebra, Trig, Calculus -- Learn to Love it as I Do
clearly, x≠0, since that would make each fraction undefined.
As you know, when dividing by a fraction, invert it and multiply. That gives you
(x-5)/(2x^2) * (6x)/(x-5)
The 2x and (x-5) cancel, leaving just 3/x, providing that x≠0