An easy way is to do this
the 2 numbers are -x and x+8 where x is an integer
we can generate lots of numbers this way
example
-1 and 9
-2 and 10
So 1/9-16z^2 this is a diffirence of two perfect squares thing
so (1/3)^2-(4z)^2
so ((1/3)-4z)((1/3)+4z)
I'm not real sure if this is right but I did my best
X = 9 sorry if x isnt what youre looking for
I believe that the answer is 20. I am not entirely sure though.