Answer:
(x - 24)(x + 3)
Step-by-step explanation:
Given
x² - 21x - 72
Consider the factors of the constant term (- 72) which sum to give the coefficient of the x- term (- 21)
The factors are - 24 and + 3, since
- 24 × + 3 = - 72 and - 24 + 3 = - 21 , then
x² - 21x - 72 = (x - 24)(x + 3) ← in factored form
