2x+5y+4z=15 7x+y+3z=14 求4x+y+2z的值
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2x+5y+4z=157x+y+3z=14求4x+y+2z的值2x+5y+4z=157x+y+3z=14求4x+y+2z的值2x+5y+4z=157x+y+3z=14求4x+y+2z的值分为A,B两式
2x+5y+4z=15 7x+y+3z=14 求4x+y+2z的值
2x+5y+4z=15
7x+y+3z=14
求4x+y+2z的值
2x+5y+4z=15 7x+y+3z=14 求4x+y+2z的值
分为A,B两式:
A:2x+5y+4z=15
B:7x+y+3z=14
将A式乘7,B式乘2,然后两式减,得到C式:
C:33y+22z=77
再将B式乘5,减去A式,得到D式
D:33x+11z=55
C与D两式相加得到E式:
E:33(x+y+z)=132
即x+y+z=4
A与B式相加得到F式
F:9x+6y+7z=29
即4x+y+2z+5x+5y+5z=29
即4x+y+2z+5(x+y+z)=29
即4x+y+2z+5*4=29
4x+y+2z=9
假设原式由第一个方程的a倍加上第二个方程的b倍所得,则
2a+7b=4
5a+b=1
b=6/11
a=1/11
验证:4a+3b=2,符合
所求式=15a+14b=9
2x+5y+4z=6,3x+y-7z=-4,x+y-z=?
2x+3y-z=9,x+y+z=15,5x-4y-z=0
X-Y-Z=0 X+Y-3Z=4 2X-5Y+7Z=21
3x+7y+4z=35,x+5y+2z=40,x+y+z=( )
{x+y+z=1 {x+3y+7z=2 {x+5y+19z=4
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z
1.{x:y:z=3:4:5 2x+3y-5z=-142.{x-y-z=-1 3x+5y+7z=11 4x-y+2z=-13.{x+y=1 x+z=0 2x+y+2z=44.{x-y+z=-3 2x-y-z=-2 -3x+y+z=-15.{x-y+z=-3 3x+y-4z=6 2x+y-z=36.{x-2y+5z=16 2x+y-5z=7 2x-y+z=38
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
三元一次方程 X-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 X=?Y=?Z=?
已知关于x y z的方程组2x-3y+5z=7 x+2y-3z=8,则4x+y-z=
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知4x-3y-6z=0,x+2y-7z=0,求5x+2y-z/2x-3y-10z
(4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=?
三元一次方程组2x+z=3 3x+y-z=8 x+3y+2z=3 5x+2y-3z=2 x+2y+z=6 7x-2y-4z=262x+z=3 3x+y-z=8 x+3y+2z=3 5x+2y-3z=2 x+2y+z=6 7x-2y-4z=26
三元一次方程解 1.{x+y-z=5 {3x+2y+z=2 {2x-2y+z=-31.{x+y-z=5 2.{9x-5y+x=-6 3.{x-y=3 4.{x+y=3 5.{4x-2y+z=7{3x+2y+z=2 {9x+y-2z=3 {x+z=7 {y+z=4 {2x-y-3z=28{2x-2y+z=-3 {-9x+3y-5z=0 {y-z=6 {z+x=5 {x+y-2z=13
{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=3 y+z-x=5 z+x-y=7 求x,y,z