解方程组4x+5y=51 6x-7y=-25
解方程组4x+5y=51 6x-7y=-25
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
解方程组﹛2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51
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()
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 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2
用加减法解方程组,6x-5y=11,-4x-4y=7
解方程组4x+5y=3.5,x-1=1.8-x-6y
1/2x-2y=-74,x-6y=-12解方程组,x/5-y/2=2,2x+3y=4解方程组