1.解方程组{x+y=7,3x+y=17
1.解方程组{x+y=7,3x+y=17
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
解二元一次方程组:{5(x+y)+3(x-y)=2{7(x+y)-3(x-y)=-6
解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3
2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组
解方程组﹛2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51
3(x+y)—4(x-y)=4,(x+y/2)+(x-y/6)=1.解方程组
解方程组:2x-3y=9(1),7x+4y=17(2)
解方程组2x-5y=7 3x+4y=17
解方程组1.x+y=4,2x+3y=7
解方程组:①3x-7y=1,5x-4y=17②23x+17y=63,17x+23y=57
解方程组 1.x=2y+3 x-3y=20 2.x-y=13 x=6y-7