解方程组一{2x-5y=1,5x+2y=17 二{x+y/2=6-x-y/3,4(x+y)-5(x-y)=2

解方程组一{2x-5y=1,5x+2y=17 二{x+y/2=6-x-y/3,4(x+y)-5(x-y)=2 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 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]=2 解方程组：x+y/2+x-y/3=6 4(x+y)-5(x-y)=12 一求方程组{6(x-y)-7(x+y)=21,2(x-y)-5(x+y)=-1的解二{2x-y-=-4,4x-5y=-2 换元法解方程组3/x+y+2/x-y=17/5 2/x+y-5/x-y=1 3(x+y)+2(x-y)=36 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用加减消元法解方程组 解方程组{(x-2)(y+3)=(x+1)(y-1) {(x+1)(y+1)=(x-1)(y+5) 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:{二分之x+y+二分之x-y=6,4(x+y)-5(x-y)=2()