How to find break-even points of profit function?

Question

Which of the following profit functions has break-even points at x = 3 and x = 11?

a) P(x) = -2 (x^2 - 28x + 66)

b) P(x) = -2 (x + 3)(x + 11)

c) P(x) = -2 (x - 3)(x + 11)

d) P(x) = -2(x^2 - 14x + 33)

I have tried to solve this by completing the square for a and d because I don't think b and c are possible answers and it did not work out I tried and tried again. If someone knows the answer could you please show/explain the steps in addition to naming the appropriate letter answer. Thanks in advance.

Answer 1

The answer is D. Funny, in my homework I have the exact same question. If you sub in 3 or 11 for x in equation D you get 0 both times.