若x^2-4x+y^2+6y+(z-3)开平方+13=0 求（xy）^2的值

若4x-3y-6z=0,x+2y-7z=0,则x+y+z/3x-y+z=? 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 求化简(x+3y+2z)(x-3y+6z)(x+3y+4z-2z)(x-3y+4z+2z) 2(x+y-z)-3(x-y+z)-5(x+y-z)+6(x-y+z) 计算 化简-(-3x-y+2z)-{-x+【4x-(x-y-z)-3x+2z} 若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z) 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-z)= 若x+y+z=3y=2z,则x/x+y+z=? x+2y=3x+2z=4y+z 求x:y:z x+y/2=z+x/3=y+z/4 x+y+z=27 数学--整式运算4(x-y+z)-2(x+y-z)-3(-x-y-z) 3x-y+z=4,2z+3y-z=12,x+y+z=6的解 三元一次方程x+y+z=0 4x+2y+z=3 9x+3y+z=6x+y+z=04x+2y+z=3 9x+3y+z=6 x/6=y/4=z/3,则(x+3y)/(3y-2z) 若x,y,z都是正数,且3x+2y-z=4,求x+y+z的取值范围.2x-y+2z=6若x，z都是正数，且3x+2y-z=4，2x-y+2z=6求x+y+z的取值范围。弄错了， (x+2y-7z)^3+(3x-4y+6z)^3-(4x-2y-z)^3 因式分解 2x-y+2z=6 3x+y-3z=-4 x+y+z=6 x+y+z=4 2x+3y-z=6 3x+2y+2z=10