x intercepts of f(x)15x^2-12x-48

Answer 1

It should probably read
f(x) = 15x^2 - 12x - 48

for x-intercepts, let f(x) or y = 0
15x^2 - 12x - 48 = 0
hint: divide each term by 3, then use the quadratic formula.
Get back to me with your answer.

Answer 2

I got 4+-sqr(336) / 10

is this right??