解方程组 x+y=7 300x+200y=1700
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
解方程组 x+y+z=-7 x-y=12 x+y-z=6
阅读下面方程组的解法:解方程组{x/5=y/7,x+y=-36
2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组
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﹛2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51
解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3
方程组x+y=-14 y+z=-7 x+y=19的解
解方程组 2x+y+z=7 x+2y+z=8 x+y+2x=9
解方程组(三分之x+y)+y=6,3(x+y)-y=24
方程组 x+5y+2=06x-7y=16x=y=
解方程组x+y+根号下x+y=12 x+xy+y=23