Question 601381
{{{4*sqrt(6)/ sqrt(30)=4*sqrt(6)/ sqrt(6*5)=4*sqrt(6)/ (sqrt(6)*sqrt(5))=4/sqrt(5)}}}
However, math teachers (and people who enjoy math) dislike seeing irrational numbers (radicals) in denominators.
So we do a transformation that we call "rationalizing."
We multiply numerator and denominator times another irrational number, to get a rational denominator.
It goes like this:
{{{4/sqrt(5)=4*sqrt(5)/(sqrt(5)-sqrt(5))=4*sqrt(5)/5}}}
Now the denominator is 5, which is a rational number, and we are happy.