已知x/3=y/4=z/5≠0,求分式x+y-z/x-y+z的值.要具体过程.

Question

已知x/3=y/4=z/5≠0,求分式x+y-z/x-y+z的值.
要具体过程.

Answer 1

设x/3=y/4=z/5=a
x=3a y=4a z=5a
x+y-z/x-y+z
=3a+4a-5a/3a-4a+5a
=2a/4a
=1/2