Hello, I am having issues with an equation involving limits and I am suppose to find the Vertical Asymptote. I thought that this equation had no Vertical asymptotes but mathlab says there is a VA at x=4

f(x=)$\displaystyle \frac{x^2-9x+20}{x^2-8x+16}$

factor

$\displaystyle \frac{(x-5)(x-4)}{(x-4)(x-4)}$

the (x-4) cancels and leaves

$\displaystyle \frac{(x-5)}{(x-4)}$

which leave a possible assymptote at x = 4,

but if i plug in 4 to the original equation

$\displaystyle \frac{4^2-9(4)+20}{4^2-8(4)+16}$ = $\displaystyle \frac{0}{0}$

which is not really an assymptote, but a hole in the graph. What am I doing wrong?