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2x+y+z=-26x=2y+z=-30x+y+2z=-28

题目详情
2x+y+z=-26 x=2y+z=-30 x+y+2z=-28
▼优质解答
答案和解析
2x+y+z=-26 (1)
x+2y+z=-30 (2)
x+y+2z=-28 (3)
(1)-(2)得:
x-y=4 (4)
(2)×2-(3)得:
x+3y=-32 (5)
(5)-(4)得:
3y+y=-36
4y=-36
y=-9
x=13
z=-16
原方程组的解是:
x=13
y=-9
z=-16