sum of roots of equation ||x - 1| - 5|= 6 is?

We have that either,

l x -1 l - 5  = 6           or  that   (l x -1 l - 5)  = - 6

Working with the first, we have

l x - 1 l   = 11     which implies that

x - 1 = 11          and       x - 1  = -11

So  x = 12          and  x = -10

And working with the second, we have

 l x - 1 l - 5  = -6

 l x - 1 l = -1      which is impossible

So,  the sum of the roots = 2