b-a=2 ,6-3a+3b=?
问题描述:
b-a=2 ,6-3a+3b=?
答
6-3a+3b
=6+3﹙b-a﹚
=6+3×2
=12
b-a=2 ,6-3a+3b=?
6-3a+3b
=6+3﹙b-a﹚
=6+3×2
=12