Answer:
The values of x for the expression is undefined is -3 or 9
Explanation:
Given function,

The values of x for which the expression is undefined is obtained when the denominator is equal to zero, from the expression it is given by;
x² - 6x - 27 = 0
Factorize the equation
x² + 3x - 9x - 27 = 0
x (x + 3) -9(x + 3) = 0
(x + 3)(x - 9) = 0
x = -3 or x = 9
Therefore, the values of x for the expression is undefined is -3 or 9