Answer:
b
Step-by-step explanation:
The graph crosses the x- axis at x = - 4 and x = 1, hence
x = - 4 and x = 1 are the zeros of the function, thus
(x + 4) and (x - 1) are the factors and
f(x) = a (x + 4)(x - 1)
The graph is a maximum therefore a = - 1
f(x) = - 1(x + 4)(x - 1) ← expand factors
f(x) = - 1(x² - x + 4x - 4)
= - 1 (x² + 3x - 4)
= - x² - 3x + 4 → b
