(3a+5)-{9a-[6a+2-(12a-10)+2(a+1)]
问题描述:
(3a+5)-{9a-[6a+2-(12a-10)+2(a+1)]
答
(3a+5)-{9a-[6a+2-(12a-10)+2(a+1)]
=3a+5-9a+6a+2-12a+10+2a+2
=-10a+19