Explanation:
you devide the upper half of a fraction with the part under it. for example
6x2+x+1
_______=6. that is asymptote
x2+2
when you multiply 6 and lower half of a fraction you get 6x2+12
if you substract that from 6x2+x+1 you get x-11
if you make x-11=0 the number that x represents is the point where the function crosses the asymptote