Answer:
x = - 3 , x = 4
Step-by-step explanation:
given the equation
x² - x - 12 = 0 ← in standard form
To factorise the left side
Consider the factors of the constant term (- 12) which sum to give the coefficient of the x- term (- 1 )
the factors are- 4 and + 3 , since
- 4 × + 3 = - 12 and - 4 + 3 = - 1 , then
x² - x - 12 = 0
(x + 3)(x - 4) = 0 ← in factored form
equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x - 4 = 0 ⇒ x = 4
The solutions to the equation are x = - 3 , x = 4