Final answer:
The Quadratic with roots at x = 1/2 and x = -4, when written in factored form, is (2x - 1)(x + 4) = 0.
Step-by-step explanation:
The Quadratic with roots at x = 1/2 and x = -4, when written in factored form, is:
(2x - 1)(x + 4) = 0
To obtain the factored form, we use the roots to identify the factors of the quadratic equation. The root x = 1/2 corresponds to the factor (2x - 1), while the root x = -4 corresponds to the factor (x + 4).
Thus, the correct option is a) (2x - 1)(x + 4) = 0.