Answer:
(x - 9)(x + 2)
Explanation:
Given
x² - 7x - 18
Consider the factors of the constant term (- 18) which sum to give the coefficient of the x- term (- 7)
The factors are - 9 and + 2, since
- 9 × 2 = - 18 and - 9 + 2 = - 7, thus
x² - 7x - 18 = (x - 9)(x + 2)