Respuesta :

Answer:

-2y + 2

Step-by-step explanation:

Let's first remove the parentheses.  (x - y + 1) becomes x - y + 1 and -(x + y - 1) becomes -x -y + 1.   Combine like terms:

x - y + 1 - x - y + 1 = -2y + 2

Answer:

-2y + 2

Step-by-step explanation:

(x - y + 1) - (x + y - 1)

remove ( )

= x - y + 1 - x - y + 1

simplify

= -2y + 2