解方程组x2+y2=73x?3y=3 x2+y2=7①3x?3y=3②,由②得:y=33x-1? ③,把③代入①得:43x2-233x-6=0,x=233±103383,x1=323,x2=-3,把x1=323代入③得,y1=12,把x2=-3代入③得,y2=-2,则原方程组的解是:x1=323y1=12,x2=?3y2=?2.