In order to answer this, we must factor x3-8x2-x+8=0
We can make 2 pairs of 2 terms in order to make the factoring easier,
(x3-8x2)+(-x+8)=0
Now we can begin to factor each pair of terms one at a time,
x2(x-8)-(x-8)=0
We can see that we have 2 (x-8)s so that is our common and we have x2-1 (we can't see the 1 because anything times 1 equals itself so we don't need to put it there).
(x2-1)(x-8)=0
Expand,
(x+1)(x-1)(x-8)=0
In order for 0=0, we must find values of x that will make 0=0