How can factoring be used to determine the vertical asymptotes or point of discontinuity of a rational function?
in a rational function the denominator may never be zero because you can’t divide by zero.
since this is something x can never equal it makes a vertical line (asymptote)
take y = 1/(x^2 + 5x + 6)
you could use the quadratic formula to find the two zeroes of x but factoring can be quicker
x^2 + 5x + 6 = (x + 3)(x + 2)
so x could not in this case equal -3 or -2 since either of those numbers would make the denominator zero