Question 93969
1) {{{x^3-x^2-20x}}}

We can first factorise it by x

{{{x^3-x^2-20x=x(x^2-x+20)}}}

and {{{x^2-x+20=(x+4)(x-5)}}}

So
{{{x^3-x^2-20x=x(x+4)(x-5)}}}

2) {{{3/x-1=6/x+2}}}
{{{(3-x)/x=(6+2x)/x}}}
Is the same as,
{{{3-x=6+2x}}}
{{{-x-2x=6-3}}}
{{{-3x=3}}}
{{{x=-1}}}