2x+3y-4z=-7 x-4y/3=2y+3z/2=2怎么解

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2x+3y-4z=-7 x-4y/3=2y+3z/2=2怎么解

x-4y/3=2y+3z/2=2
x=2+4y/3
z=(4-4y)/3
2x+3y-4z=-7
2*(2+4y/3)+3y-4(4-4y)/3=-7
y=5/11
x=86/33
z=8/11

2x+3y-4z=-7 (1)
x-4y/3=2y+3z/2=2
所以x-4y/3=2
2y+3z/2=2
所以
3x-4y=6 (2)
4y+3z=4 (3)
(1)×3-(2)×2
6x+9y-12z-6x+8y=-21-12
17y-12z=-33 (4)
(3)×4+(4)
16y+12z+17y-12...

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2x+3y-4z=-7 (1)
x-4y/3=2y+3z/2=2
所以x-4y/3=2
2y+3z/2=2
所以
3x-4y=6 (2)
4y+3z=4 (3)
(1)×3-(2)×2
6x+9y-12z-6x+8y=-21-12
17y-12z=-33 (4)
(3)×4+(4)
16y+12z+17y-12z=16-33
33y=-17
y=-17/33
代入(4)
z=(17y+33)/12=200/99
代入(2)
x=(6+4y)/3=130/99
所以x=130/99,y=-17/33,z=200/99

收起

x-4y/3=2y+3z/2=2
x=2+4y/3
z=(4-4y)/3
2x+3y-4z=-7
2*(2+4y/3)+3y-4(4-4y)/3=-7
y=5/11
x=86/33
z=8/11