Identify all values of x for which x2 16x2 6x 27x 1 is u

Identify all values of x for which x^2 - 16/(x^2 - 6x - 27)(x + 1) is undefined. A -3, -1 B -3, -1, 9 C 3, 1, -9 D -1

Answer for 5, 6 and 7 are correct and answer for 8 is wrong

r^2 + 6r + 8 = (r + 2)*(r + 4)

r^-4 = (r - 2)*(r + 2)

So correct option is B.

y = 4^x - 1

for y-intercept, x = 0

y = 4^0 - 1 = 0

So correct option is A.