Question

三元一次方程组x+y+z=1解三元一次方程组x+y+z=1x-y+z=3x+y-z=-1

Answer 1

x+y+z=1 (1)

x-y+z=3 (2)

x+y-z=-1 (3)

(2)-(1)得 -2y=2

y=-1

得 x+z=2

x-z=0

解得 x=1 z=1

终上所述 x=1 y=-1 z=1