If `x + y + z= 0`, then `x^3 + y^3 + z^3` is equal to :

If x+y+z=0 then x^3+y^3+z^3+3xyz equal to

If x-2y+2z=0, then x^(3)-8y^(3)+8z^(3) is equal to

If x+y+z=0 , then x^3+y^3+8 equals

Let x, y, z be non-zero real numbers such that x/y + y/z + z/x = 7 and y/x + z/y + x/z = 9 , then (x^3)/y^3 + y^3/z^3 + z^3/x^3 - 3 is equal to