6x-3y=31 2x-5x=-20 解方程组用加减消元法

x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 解联立方程组 x/x+y=5/8 x/x+y+6=2/3 3x*5y+2x*6y=2.7*(3x+2x)怎么解 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 解方程组;x+y/2=x-y/3=6 4(x+y)-3(x-y)=-20 解方程组 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2 解二元一次方程：x+y/2+x-y/3=6 4(x+y)-5(x-y)=2 解二元一次方程组{x+y/2+x-y/3=6,4(x+y)-2=5(x-y) 解方程组2分之x+y+3分之x-y=6 4(x+y)-5(x-y)=2 解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4 解方程组：x+y/2+x-y/3=6 4(x+y)-5(x-y)=12 解方程组：3(x+y)+2(x-y)=11,6(x+y)-5(x-y)=13. 解方程组：x+y/2+x-y/3=6,（x+y）+5（x-y）=38 谢. 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)