Разложите на множители многочлен: xy-by+2y+ax-ab+2a.

\[\text{xy} - by + 2y + ax - ab + 2a =\]

\[= y(x - b) + a(x - b) + 2(a + y) =\]

\[= (x - b)(a + y) + 2(a + y) =\]

\[= (a + y)(x - b + 2).\]