(x+y) prop z,(y+z) prop x then prove that (z+x) prop y ?thanks

1 Answer
Jun 9, 2017

Given

x+ypropz

=>x+y=mz.......[1], where m = proportionality constant

=>(x+y)/z=m

=>(x+y+z)/z=m+1 ....[2]

Again

y+zpropx

=>y+z=nx........[3], where n = proportionality constant

=>(y+z)/x=n

=>(x+y+z)/x=n+1 ......[4]

Dividing [2] by [4]

x/z=(m+1)/(n+1)=k(say)

=>x=kz......[5]

By [1] and [5] we get

kz+y=mz

=>y=(m-k)z

=>y/z=(m-k)......[6]

Dividing [2] by [6] we get

(x+y+z)/y=(m+1)/(m-k)=c " another constant"

=>(x+y+z)/y-1=c -1

=>(x+z)/y=c -1="constant"

Hence

z+xpropy

Proved