Answer:
x = - 6, x = 7
Step-by-step explanation:
Begin by equating to zero
x² - x - 42 = 0
Consider the factors of the constant term (- 42) which sum to give the coefficient of the x- term (- 1)
The factors are - 7 and + 6 , since
- 7 × + 6 = - 42 and - 7 + 6 = - 1 , then
(x - 7)(x + 6) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 6 = 0 ⇒ x = - 6
x - 7 = 0 ⇒ x = 7
