Verified answer

this is the "difference of squares" where a²-b²=(a-b)(+b). In this problem, however:

a = x and b = y-11.

Therefore, it factors as follows:

(x + y - 11)(x - y + 11)

that's it! ;)

Hmm yea I had to think about it for a bit :P

(x^2) - (y-11)^2

x^2 - (y-11)(y-11)

x^2 - y^2 -11y -11y + 121

x^2 - y^2 - 22y + 121

I'm not sure at how to explain what goes on in-between

-(y - x - 11) (y + x -11) = 0 < final answer

or (x + y - 11)(x - y + 11)