解三元一次方程组x+2+y+z=10,2x+3y-z=3,3x+2y+2z=17x+2+y+z=10,{2x+3y-z=3,3x+2y+2z=17

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解三元一次方程组x+2+y+z=10,2x+3y-z=3,3x+2y+2z=17x+2+y+z=10,{2x+3y-z=3,3x+2y+2z=17
解三元一次方程组x+2+y+z=10,2x+3y-z=3,3x+2y+2z=17
x+2+y+z=10,
{2x+3y-z=3,
3x+2y+2z=17

解三元一次方程组x+2+y+z=10,2x+3y-z=3,3x+2y+2z=17x+2+y+z=10,{2x+3y-z=3,3x+2y+2z=17
x+2+y+z=10,------- ①
2x+3y-z=3,------- ②
3x+2y+2z=17------- ③
①+②
3x+4y+2 = 13
3x+4y = 11------- ④
②×2 + ③
7x+8y = 23------- ⑤
⑤×2 - ④
x = 1
代入④
3 + 4y = 11
y = 2
将x = 1、y = 2代入①
1+2+2+z = 10
z = 5

x+2y+z=10(1)
2x+3y-z=3(2)
3x+2y+2z=17(3)
(1)+(2)得3x+5y=13(4)
2(2)+(3)得7x+8y=23(5)
(4)和(5)得21x+35y=91(6)
21x+24y=69(7)
(6)-(7)得11y=22,所以y=2
y=2代入(4)得y=2<...

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x+2y+z=10(1)
2x+3y-z=3(2)
3x+2y+2z=17(3)
(1)+(2)得3x+5y=13(4)
2(2)+(3)得7x+8y=23(5)
(4)和(5)得21x+35y=91(6)
21x+24y=69(7)
(6)-(7)得11y=22,所以y=2
y=2代入(4)得y=2
x=1,y=2代入(1)得z=5
所以解得x=1,y=2,z=5

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