3x-5y+2z=1 4x+5y-z=5 x-5y+3z=-2

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3x-5y+2z=1 4x+5y-z=5 x-5y+3z=-2

3x-5y+2z=1 4x+5y-z=5 x-5y+3z=-2
3x-5y+2z=1 4x+5y-z=5 x-5y+3z=-2

3x-5y+2z=1 4x+5y-z=5 x-5y+3z=-2
3x-5y+2z=1 (1)
4x+5y-z=5 (2)
x-5y+3z=-2 (3)
(1)+(2)得7x+z=6 (4)
(2)+(3)得5x+2z=3 (5)
(4)X2-(5)得9x=9 .所以x=1
将x=1代入(4)得z=-1
将x=1、z=-1代入(1)得y=0
即此题结果:x=1、y=0、z=-1

3x-5y+2z=1 ①
4x+5y-z=5 ②
x-5y+3z=-2 ③
①+②,得7x+z=6 ④
①-③,得2x-z=3 ⑤
④+⑤,得9x=9,解得x=1
代入⑤,解得z=-1
代入①,解得y=0

1式-3式有2x-z=3 则4x-2z=6
2式+4式有5x+2z=3
于是得出9x=9 x=1
z=-1
y=0

X=1 Y=0 Z=-1