17x^3+7x^2-4x-44 how do you solve this

17x^3 + 7x^2 - 4x - 44 = 0
17x^3 + 7x^2 - 4x = 44
x (17x^2 + 7x -4) = 44
x = 44, or complete the square on the quadratic...
17x^2 + 7x -4+4 = 44+4
17x^2 + 7x = 48
(17x^2 + 7x)/17 = 48/17
x^2 + 7/17x = 48/17
(x + 7/34)^2 - (49/1156) = (48/17)-(49/1156)
(x + 7/34)^2 - (49/1156) + (49/1156) = (48/17)•(68/68) + (49/1156)
(x + 7/34)^2 = (48/17)•(68/68) + (49/1156)
(x + 7/34)^2 = (3264/1156) + (49/1156)
(x + 7/34)^2 = (3313/1156)
(x + 7/34)^2 = 2.866
SR [(x + 7/34)^2] = SR (2.866)
(x + 7/34) = +/- 1.6929
(x + .2059) = +/- 1.6929
x + .2059 = +1.6929, and x + .2059 = - 1.6929
x + .2059 = +1.6929--> x = 1.6929-.2059 --> x = 1.487

x + .2059 = - 1.6929--> x = -1.6929 + -.2059 --> x = -1.899
So roots or solutions are:
x = 44, x = 1.487, & x = -1.899

It says in the questions that it is 6.5?