Answer:
y = x² - 3x - 4
Step-by-step explanation:
Given that the x- intercepts are x = - 1 and x = 4, then the corresponding factors are
(x + 1) and (x - 4) and the quadratic is the product of the factors, that is
y = (x + 1)(x - 4) ← expand using FOIL
y = x² - 3x - 4