Let the cubic be in the form f(x) = ax^3 + bx^2 + cx + d.
We have four points and four variables, so plug them in:
(3, -4) ==> 27a + 9b + 3c + d = -4
(-1, 2) ==> a - b + c - d = 2
(0, 0) ==> d = 0
(7, 5) ==> 343a + 49b + 7c + d = 5
Use WolframAlpha or a similar program to solve for a, b, c, and d.