解方程组 {6+x+y+7=55、60+20x+50y+700=2530
解方程组 x+y+z=-7 x-y=12 x+y-z=6
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
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 1.x=2y+3 x-3y=20 2.x-y=13 x=6y-7
解方程组(三分之x+y)+y=6,3(x+y)-y=24
解方程组x+y+√(x+y)=20;x²+y²=136
解方程组 x=3y-6 0.8(x+y)=x+y-13.6
解方程组X+Y/2=3X-2Y=10+6X+Y/4
解方程组:{x+|3x-y|+3y=15 2x+y=6
阅读下面方程组的解法:解方程组{x/5=y/7,x+y=-36