Answer:
x = -1/5, x = i sqrt(30)/5, x = -i sqrt(30)/5
Step-by-step explanation:
25x^3 + 5x^2 + 30x + 6 = 0
5x^2(5x + 1) + 6(5x + 1) = 0
(5x + 1)(5x^2 + 6) = 0
5x + 1 = 0
5x = -1
x = -1/5
5x^2 + 6 = 0
5x^2 = -6
x^2 = -6/5
x = +/- sqrt(-6/5)
x = +/- i * sqrt(30)/5
x = i sqrt(30)/5 or x = -i sqrt(30)/5
