解方程组x+2y-3z=0,2x+3z=-1,3x+y+2z=4谢谢

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解方程组x+2y-3z=0,2x+3z=-1,3x+y+2z=4谢谢

解方程组x+2y-3z=0,2x+3z=-1,3x+y+2z=4谢谢
解方程组x+2y-3z=0,2x+3z=-1,3x+y+2z=4谢谢

解方程组x+2y-3z=0,2x+3z=-1,3x+y+2z=4谢谢
(3)×2-(1)得
5x+7z=8 (4)
(4)×3-(2)×7得
x=31
把 x=25代入(2)得
3z=-63
∴z=-21
把x=31,z=-21代入(1)得
31+2y+63=0
∴y=-47
∴x=31
y=-47
z=-21

解方程组
x+2y-3z=0, (1)
2x+3z=-1, (2)
3x+y+2z=4 (3)
解,得:
由(1)+(3)得:
3x+y==-1 (4)
由(2)...

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解方程组
x+2y-3z=0, (1)
2x+3z=-1, (2)
3x+y+2z=4 (3)
解,得:
由(1)+(3)得:
3x+y==-1 (4)
由(2)*2-(3)*3得:
5x+3y==14 (5)
由(4)*3-(5)得:
4x==-17
x==-17/4
y==47/4
z==4.5

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x + 2y - 3z = 0 ①
2x + 3z = -1 ②
3x + y + 2z = 4 ③
③ × 2 - ①得
5x + 7z = 8 ④
④ × 3 - ② × 7得

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x + 2y - 3z = 0 ①
2x + 3z = -1 ②
3x + y + 2z = 4 ③
③ × 2 - ①得
5x + 7z = 8 ④
④ × 3 - ② × 7得
x = 31
把 x = 31代入 ②中得
2 × 31 + 3z = -1
62 + 3z = -1
3z = -1 - 62
3z = - 63
z = -21
把x = 31,z = -21代入①得
31 + 2y - 3 ×(-21) = 0
31 + 2y + 63 = 0
2y + 94 = 0
2y = - 94
y = - 47
∴ 原方程组的解为
x = 31
y = -47
z = -21

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