x\(^3\) - 19x - 30

 test x = 5
5\(^3\) −19(5) − 30 = 125 − 95 − 30 = 0

(x - 5) is a factor.

x\(^3\) - 19x - 30 divided by (x - 5) = x\(^2\) + 5x + 6 

factorizing x\(^2\) + 5x + 6, we have (x+2)(x+3)

(x+2)(x+3)(x - 5) = 0 

x = -2, -3, and 5.