1) a(x+y)+2x+2y-a(x+y)+2(x+y) =
(x+y)(a+2)
a(x+y) + 2x + 2y - a(x+y) + 2(x+y) = a(x+y) - a(x+y) + 2x + 2y + 2x + 2y = 4x + 4y = 4(x+y)
Ответ: 4(x+y)