According to the rational root theorem, the following are potential roots of f(x) = 60x2 – 57x – 18. -6/5, -1/4, 3, 6 which is an actual root of f(x)?

As for Rational Root Theorem, we substitute the given choices in the equation and if the value of f(x) is equal to 0 then, the certain choice is a root of the equation.

(1)     -6/5 :    f(x) = 60(-6/5)^2 - 57(-6/5) - 18  = 136.8
(2)     -1/4:     f(x) = 60(-1/4)^2 - 57(-1/4) - 18 = 0
(3)         3:     f(x) = 60(3)^2 - 57(3) - 18 = 351
(4)         6:     f(x) = 60(6)^2 -57(6) - 18 = 1800

Thus, the answer is the second choice.