已知a+b-c=0,2a-b+2c=0(c不等于0),求(3a-2b+5c0/(5a-3b+2c)的值.

由a+b-c=0,2a-b+2c=0可得
a=-c/3,b=4c/3
3a-2b+5c=-c-8c/3+5c=(4-8/3)c=4c/3
5a-3b+2c=-5c/3-4c+2c=(-5/3-2)c=-11c/3
(3a-2b+5c)/(5a-3b+2c)=-4/11