(3a+5)-{9a-[6a+2-(12a-10)+2(a+1)]}

分类: 作业答案 • 2022-04-07 21:29:48

问题描述：

答

(3a+5)-{9a-[6a+2-(12a-10)+2(a+1)]}
=(3a+5)-[9a-(6a+2-12a+10+2a+2)]
=(3a+5)-[9a-(-4a+12)]
=3a+5-(9a+4a-12)
=3a+5-(13a-12)
=3a+5-13a+12
=-10a+17