Answer:
(x - 9)(x + 1)
Explanation:
Given
x² - 8x - 9
Consider the factors of the constant term (- 9) which sum to give the coefficient of the x- term (- 8)
The factors are - 9 and + 1, since
- 9 × 1 = - 9 and - 9 + 1 = - 8, thus
x² - 8x - 9 = (x - 9)(x + 1)