2x+y=4,x+2y=5解方程组（用加减消元法）

解方程组 3x加2y加5z=2 x-2y-z=6 4x加2y-7z=30 解方程组:2分之2x+y加3分之2x-y=1,4*(2x+y)-5(2x-y)=8, 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 解方程组3x+5(x+y)=2 3y-2(x+y)=4 用图像法解方程组x+2y=4,x-y=1有图的加50分 解方程组 x+y/5+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/2=7,4(x+y)-5(x-y)=2... 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组 解方程组 {3(x+y)-4(x-y)=11 {2(x-y)+5(x+y)=27 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 {3(x+y)-4(x-y)=11 {2(x-y)+5(x+y)=27全过程、快 解方程组：x+y/2+x-y/3=6 4(x+y)-5(x-y)=12 x+y/2+x-y/3=6,4(x+y)-5(x-y)=2用加减消元法解方程组 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