x/5=y/3 x/7=z/3 2x-y-z=34

问题描述:

x/5=y/3 x/7=z/3 2x-y-z=34

由已知得3x=5y=7z y=3/5x z=3/7x
将一直带入2x-y-z=34中
2x-3/5x-3/7x=34
解得x=35 y=21 z=15