解方程组{5x-6y=9 7x-4y=-5

解方程组{5x-6y=9 7x-4y=-5 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 解方程组：｛4x+5(x-y)=30,4y-3(x-y)=6 y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,无 解方程组 x+y/5+x-y/2=7 4(x+y)-5(x-y)=2 解方程组：{4/x+y+6/x-y=3 9/x-y-1/x+y=1} 解方程组{4/x+y+6/x-y=3, 9/x-y-1/x+y=1 解方程组6(x-y)-7(x+y)=21 2(x-y)-5(x+y)=-1 解方程组x+y/2+x-y/2=7,4(x+y)-5(x-y)=2... 解方程组 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2 解二元一次方程组{x+y/2+x-y/3=6,4(x+y)-2=5(x-y) 解方程组:{二分之x+y+二分之x-y=6,4(x+y)-5(x-y)=2() 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 用代入法解此方程组：（x+y)/2+(x-y)/3=6 4(x+y)-5(x-y)=2求方程组的正整数解：x+y+z=7 2x+3y+4z=20 2+3x/5+4y=9,4+6y-y=1解方程组 帮忙解一些方程组(1)3x-2y=6 2x+3y=17 (2)5x+6y=15.2 3x-2y=-0.4(3)2(x+y)-3y=7 4(x-9)=3(y-2)(4)3(x+y)-4(x-y)=4 x+y/2+x-y/6=1