Question 252914
The equation i think is this:
{{{(x^2+x)/(sqrt(5x)+x)}}} 
step 1: to rationalize we multiply by a conjugate: sqrt(5x) - x in both numerator and denominator as:
{{{(x^2+x)/(sqrt(5x)+x)}}} * {{{(sqrt(5x)-x) / (sqrt(5x) - x)}}}
By foil we get
{{{X^2*sqrt(5x) - x^3 + x*sqrt(5x) - x^2}}} / {{{5x - x^2}}}
Now, notice we can factor our, or cancel an x from everything. So, we get

{{{X*sqrt(5x) - x^2 + sqrt(5x) - x}}} / {{{5 - x}}}