你好！！！ x^2+3xy+y^2+5x+7y+6=x�0�5+(3y+5)x+(y�0�5+5y+6)=x�0�5+(3y+5)x+(y+2)(2y+3)=x�0�5+[(y+2)+(2y+3)]x+(y+2)(2y+3)=(x+(y+2))(x+(2y+3))=(x+y+2)(x+2y+3)； 祝你学业进步！！
=(x+2y+3)(x+y+2)
