已知a/2=b/3=c/4,求(a+2b+3c)/(a-2b-3c)

问题描述:

已知a/2=b/3=c/4,求(a+2b+3c)/(a-2b-3c)

a/2=b/3=c/4
b=3/2a
c=2a
(a+2b+3c)/(a-2b-3c)
=(a+3a+6a)/(a-3a-6a)
=10a/-8a
=-5/4