解方程组2x+3y=13,5x-7y=-11
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
解方程组 {3(x+y)-4(x-y)=11 {2(x-y)+5(x+y)=27全过程、快
解方程组 {3(x+y)-4(x-y)=11 {2(x-y)+5(x+y)=27
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:4x+5y=-3,2x-7y=-11
解方程组x+y/3=x-y/4 2x+3y=11
解方程组: {3x+2y=13 3x-2y=5 {x-y/3=x+y/2+1 2x-5y=9
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
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)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组
解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4