+128475 Subtract 4x from both sides
x^3 > 5x^2 rearrange as
x^3 - 5x^2 > 0 factor as
x^2 ( x - 5) > 0
Set as an equality
x^2 ( x - 5) = 0
The possible solution intervals are x = ( -inf , 0) or ( 0, 5) or ( 5 , inf)
If we let x < 5 , the first two intervals do not solve the original inequality
So......the solution is ( 5, inf)
