Factor the polynomial completely
x^2 + 18
a) (x + 2)(x + 9)
b) (x - 9)(x - 2)
c) (x + 9)(x - 9)
d) it cannot be factored
The correct answer is d) it cannot be factored.
The given polynomial, x^2 + 18, does not contain any common factors between its terms. Additionally, there are no integer values that can be multiplied together to equal 18 and added to equal 0 (the coefficient of x^2 is 1 in this case). Therefore, the polynomial cannot be factored further.