爱吃橙的豆豆
幼苗
共回答了19个问题采纳率:94.7% 举报
一:x+y=0 (1)
{y+z= -1 (2)
{z+x=-1 (3)
(1)+(2)+(3)得
2(x+y+z)=-2
x+y+z=-1 (4)
(4)-(1)得 z=-1
(4)-(2)得 x=0
(4)-(3)得 y=0
二:(x+y= -14 (1)
{y+z= -7 (2)
{z+x=9 (3)
(1)+(2)+(3)得
2(x+y+z)=-12
x+y+z=-6 (4)
(4)-(1)得 z=8
(4)-(2)得 x=1
(4)-(3)得 y=-15
1年前
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