Find all real solutions to the equation

x^4 - 40x^3 + 600x^2 - 4000x + 9375 = 0

Factor is to get \((x-5)(x-15)(x^2-20x+125) \) which has solutions of \(x=5,x=15,x=10-5i,x=10+5i\)

real solutions would be x=5, x=15. complex solutions would be x=10-5i, x=10+5i