Question: Which of the following is the factorization of x² - 9x + 20?

Options:

1. (x - 4)(x - 5)
2. (x + 4)(x + 5)
3. (x - 2)(x - 10)
4. (x + 2)(x + 10)

Correct Answer: (x - 4)(x - 5)

Solution:

x² - 9x + 20 = (x - 4)(x - 5) because -4 and -5 add to -9 and multiply to 20.