Final answer:
The x-values of the inflection points are 2 and 8.
Step-by-step explanation:
To find the x-values of the inflection points, we need to determine the values of x that make the second derivative equal to zero. Given f''(x) = x^2 - 10x + 16, we set x^2 - 10x + 16 = 0. Solving this quadratic equation, we find that the roots are x = 2 and x = 8. Therefore, the x-values of the inflection points are (2,8).