Answer:
(x+y)(x-y-1)
Step-by-step explanation:
x²-y²-x-y= (x+y)(x-y)-(x+y)= (x+y)(x-y-1)
(x + y)(x - y - 1)
x² - y² - x - y =
= (x - y)(x + y) - (x + y)
= (x + y)(x - y - 1)
use a² - b² = (a - b)(a + b)