Answer:
x = 5 or x = -4
Step-by-step explanation:
3x^2 - 3x - 60 = 0
Factor out 3 from the left side.
3(x^2 - x - 20) = 0
Divide both sides by 3.
x^2 - x - 20 = 0
Factor the trinomial.
(x - 5)(x + 4) = 0
x - 5 = 0 or x + 4 = 0