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