x/2=y/3=z/4,求x+2y-3z/3y-z的值.

问题描述:

x/2=y/3=z/4,求x+2y-3z/3y-z的值.

设x/2=y/3=z/4=t
则x=2t,y=3t,z=4t
代入得代数式得
原式=(2t+2*3t-3*4t)/(3*3t-4t)=-4t/5t=-4/5