How do you find the vertical, horizontal and slant asymptotes of: y=(2x )/ (x-5)?

1 Answer
Jun 28, 2016

vertical asymptote x = 5
horizontal asymptote y = 2

Explanation:

For this rational function (fraction) the denominator cannot be zero. This would lead to division by zero which is undefined. By setting the denominator equal to zero and solving for x we can find the value that x cannot be. If the numerator is also non-zero for such a value of x then this must be a vertical asymptote.

solve : x - 5 = 0 rArr x = 5 is the asymptote

Horizontal asymptotes occur as

lim_(xto+-oo) ytoc" (a constant)"

divide terms on numerator/denominator by x

((2x)/x)/(x/x-5/x)=2/(1-5/x)

as xto+-oo, yto2/(1-0)

rArry=2" is the asymptote"

Slant asymptotes occur when the degree of the numerator > degree of the denominator. This is not the case here ( both degree 1 ) Hence there are no slant asymptotes.
graph{(2x)/(x-5) [-20, 20, -10, 10]}