二元一次方程组计算题要解题过程!谢谢答:1,x-y=2 xy=15 (x=5,y=3)2,x+y=6 x-y=2 (4,2)3,x+y=11,xy=30 (x=5,y=6,x=6,y=5)4,x+y=13,xy=42 (x=6,7,y=7,6)5,x+y=11,x-y=1 (x=6,y=5)6,x+y=12,xy=35 (x=5,7,y=7,5)7,x+y=5,xy=6 (x=2,3,y=3,2)8,x-y=5,xy=36 (x=...
求二元一次方程组,要简单的计算题答:xy=15 (x=5,y=3)2,x+y=6 x-y=2 (4,2)3,x+y=11,xy=30 (x=5,y=6,x=6,y=5)4,x+y=13,xy=42 (x=6,7,y=7,6)5,x+y=11,x-y=1 (x=6,y=5)6,x+y=12,xy=35 (x=5,7,y=7,5)7,x+y=5,xy=6 (x=2,3,y=3,2)8,x-y=5,xy=36 (x=6,y=1)9,x...