Răspuns:
Sper ca te-am ajutat!
Coroana???
[tex]\it x\circ y=xy+3x+3y+6=xy+3x+3y+9-3=(xy+3y)+(3x+9)-3=\\ \\ =y(x+3)+3(x+3)-3=(x+3)(y-3)-3[/tex]