解 2X+Y +3Z=1 3X-2Y+2Z=2-4X+4Y-Z= -1

问题描述:

解 2X+Y +3Z=1 3X-2Y+2Z=2-4X+4Y-Z= -1

2X+Y +3Z=1 (1)
3X-2Y+2Z=2 (2)
-4X+4Y-Z= -1 (3)
(1)*2+(2)得
7X+8Z=4 (4)
(2)*2+(3)得
2X+3Z=3 (5)
(4)*2-(5)*7得
Z=2.6
代入(5)得
X=-2.4
代入(1)得
Y=-2