如果a-b=5,那么3a+7+5b-6(a+1/3b)=_.
问题描述:
如果a-b=5,那么3a+7+5b-6(a+
b)=______. 1 3
答
3a+7+5b-6(a+
b),1 3
=3a+7+5b-6a-2b,
=-3a+3b+7,
=-3(a-b)+7,
=-3×5+7,
=-8.
故答案是:-8.