Factor x2−y2+6x+9x^2 - y^2 + 6x + 9x2−y2+6x+9.
(x+y+3)(x−y+3)(x + y + 3)(x - y + 3)(x+y+3)(x−y+3)
(x−y+3)(x+y−3)(x - y + 3)(x + y - 3)(x−y+3)(x+y−3)
(x+3)2−y2(x + 3)^2 - y^2(x+3)2−y2
(x+y)(x−y)+9(x + y)(x - y) + 9(x+y)(x−y)+9