The values of x are 4, -4, and -2.
We can solve this by simply factorising the (x² - 16) bracket into a difference of two squares, to give us (x + 4)(x - 4), and then setting each bracket equal to 0.
When x + 2 = 0, x = -2
When x + 4 = 0, x = -4
When x - 4 = 0, x = 4
I hope this helps!