(3x+2y-5z+1)(-3x+2y-5z-1)
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.
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
x+y+z=2 x-3y+2z=1 2x+2y+z+5 要具体步骤..
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
(1){x-y=2 z-x=3 y+z=-1 (2){x-y-z=2 3x+5y+7z=24 4x-y+2z=26
解下列方程组(1)3x-y+z=3 2x+y-3z=11 x+y+z=12(2)5x-4y+4z=13 2x+7y-3z
已知3x=4Y,5Y=6Z,求 (1)x:y:z;(2)x+y/y+z.
(1)3x+4z=7;2x+3y+z=9;5x-9y+7z=8 (2)3x+4y+z=14;x+5y+2z=17;2x+
x/2=y/3=z/5 x+3y-z/x-3y+z
{5x-3y+z=2{5x+2y-4z=3{-5x+y-z=2 {x-y-z=-1{3x+5y+7z{4x-y+2x=-
1.(x+y-z)+(x-y+z)-(x-y-z) 2.2x-(3x-2y+3)-(5y-2)