subtract 4x^2 from both sides
- get 1x^2
-add 17x on both sides = get 6x on the left side
-subtract 6 from both sides = -2 on the right side
if you do this you SHOULD get ,
x^2 + 6x - 2 = 0
plug into quadratic formula (search up) : where ax^2 + bx + c is the formate ( a = 1. b = 6 c = -2 )
we should get the solution: -3+sqrt(11) or -3-sqrt(11) and they represent a and b
1/ (-3+sqrt(11))^3 + 1/ (-3-sqrt(11))^3 = 63/2 or 31.5
see if you can get it!
and someone please check my work