Factor x2−3x−28x^2 - 3x - 28x2−3x−28.
(x−7)(x+4)(x - 7)(x + 4)(x−7)(x+4)
(x−4)(x+7)(x - 4)(x + 7)(x−4)(x+7)
(x−1)(x−28)(x - 1)(x - 28)(x−1)(x−28)
(x−2)(x−14)(x - 2)(x - 14)(x−2)(x−14)