x/2=y/3=z/4,5x+2y-3z=8

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x/2=y/3=z/4,5x+2y-3z=8
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x/2=y/3=z/4,5x+2y-3z=8
x/2=y/3=z/4,5x+2y-3z=8

x/2=y/3=z/4,5x+2y-3z=8
设x/2=y/3=z/4=k
∴x=2k,y=3k,z=4k 设一个中间变量k,方便解决问题
把x=2k,y=3k,z=4k 代入5x+2y-3z=8得
∴10k+6k-12k=8
4k=8
k=2
把k=2代入x=2k,y=3k,z=4k得
x=4
y=6
z=8

x/2=y/3=z/4
y=3/2x
z=2x
5x+2y-3z=8
5x+2*3/2x-3*2x=2x=8
x=4
y=3/2x=4*3/2=6
z=2x=2*4=8

收起 x/2=y/3=z/4, 可设 x y z 分别为 2k 3k 4k
5x+2y-3z=8 = 10k+6k-12k = 4k
k=2
x= 4 y= 6 z=8