2x²+5xy+2y²+3x-3y-9
=(2x+y)(x+2y)+3(x-y)-9
=(2x+y-3)(x+2y+3)
6x²+13xy+6y²+5x+5y+1
=(2x+3y)(3x+2y)+5(x+y)+1
=(2x+3y+1)(3x+2y+1)