Answer:
(x + 6)(x - 2)
Explanation:
f(x) = x² + 4x - 12
consider the factors of the constant term (- 12) which sum to give the coefficient of the x- term (+ 4)
the factors are + 6 and - 2 , since
6 × - 2 = - 12 and 6 - 2 = + 4 , then
x² + 4x - 12 = (x + 6)(x - 2) ← in factored form