解方程x+2y+z=13,x+y+2z=14,3x-y+3z=18.

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解方程x+2y+z=13,x+y+2z=14,3x-y+3z=18.

解方程x+2y+z=13,x+y+2z=14,3x-y+3z=18.
解方程x+2y+z=13,x+y+2z=14,3x-y+3z=18.

解方程x+2y+z=13,x+y+2z=14,3x-y+3z=18.
X+2Y+Z=13 (1)
X+Y+2Z=14 (2)
3X-Y+3Z=18 (3)
(2)+(3):4X+5Z=32(4)
2(2)-(1):X+3Z=15(5)
4(5)-(4):7Z=28
Z=4
则X=3,Y=3

X=3 Y =3 Z=4
联立方程组就可以X+2Y+Z=13 (1)
X+Y+2Z=14 (2)
3X-Y+3Z=18 (3)
(2)+(3):4X+5Z=32(4)
2(2)-(1):X+3Z=15(5)
4(5)-(4):7Z=28
Z=4
则X=3,Y=3
将财富给我吧,我急用谢谢

x+2y+z=13, (1)
x+y+2z=14, (2)
3x-y+3z=18. (3)
(1)-(2) 得 y-z=-1
y=z-1 (4)
代入(2)得 x+z-1+2z=14
x=15-3z (5)
把(4)(5)代入(3)
3(15-3z)-z+1+3z=18
则 z=4
x=3, y=3,z=4