Odpowiedź :
[tex]\left \{ {{xy=0/:y} \atop {x^2+y^2=9}} \right. \\\left \{ {{x=0} \atop {0^2+y^2=9}} \right. \\\left \{ {{x=0} \atop {y^2=9} \right. \\\left \{ {{x=0} \atop {y=3}} \right. \\\\Odp. D[/tex]
[tex]\left \{ {{xy=0/:y} \atop {x^2+y^2=9}} \right. \\\left \{ {{x=0} \atop {0^2+y^2=9}} \right. \\\left \{ {{x=0} \atop {y^2=9} \right. \\\left \{ {{x=0} \atop {y=3}} \right. \\\\Odp. D[/tex]