2(2x-3y-z)-{4x-2[2y-3(x-z)]}-4x-6(y+z) 去括号 合并同类项
合并同类项 2x—3(x—2y+3z)+2(3x—3y+2x)
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
1.x+y=16,y+z=12,z+x=102.3x-y+z=4,2x+3y-z=12,x+y+z=63.x+y+z=6
(x+2y-7z)^3+(3x-4y+6z)^3-(4x-2y-z)^3 因式分解
x+y+z=4 2x+3y-z=6 3x+2y+2z=10
2x-y+2z=-17 3x+y-3z=-4 x+y+z=6
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
{2x+3y-4z=-5 x+y+z=6 x-y+3z=10
解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6}
解方程{3x -y+z=4 2x+3y-z=12 x+y+z=6