解方程组：4x+7y=-19 4x-5y=17

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/2=7,4(x+y)-5(x-y)=2... 解方程组：4x+7y=-19 4x-5y=17 解方程组8y+5x=84y-3x=7 方程组 因式分解 4x^3-4x^2y-(x-y) 解方程组 3x-5y=7 4x+2y=5解方程组3x-5y=74x+2y=5 解方程组：｛4x+5(x-y)=30,4y-3(x-y)=6 解方程组3x+5(x+y)=2 3y-2(x+y)=4 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 3(x-y)+5(x-y)=19 4(x+y)-2(x-y)=-1解方程组是3（x+y) 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 解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3 解方程组 X+Y/2+X-Y/3=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 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 {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 5(x+y)-2(x-y)=4