答：5(x+2)=2a+3与(3a+1)x/3=a(5x-3)/5两方程的解相同
x+2=(2a+3)/5
x=(2a+3)/5-2
(3a+1)x/3=a(5x-3)/5
两边同乘以15得：5(3a+1)x=3a(5x-3)
15ax+5x=15ax-9a
5x=-9a
x=-9a/5
所以：x=(2a+3)/5-2=-9a/5
所以：2a+3-10=-9a
2a+9a=10-3
11a=7
a=7/11