f (x) = xcubed + axsquared + bx + c.

If f(-3) = 0, f (4) = 0 and 4f (0) = 5f (1)

find the values of the constants a , b and c.

I've made 2 linear simultaneous equations from the f -3 = 0 and f 4 = 0

but for the 4f 0 = 5f 1 I dont know what to do.

Can anyone help me please?

Thanks