3m-4n+2m+3n怎么算啊.我刚刚学有理数的加减法,不怎么熟练,

问题描述:

3m-4n+2m+3n
怎么算啊.我刚刚学有理数的加减法,不怎么熟练,

3m-4n+2m+3n
=(3m+2m)-4n+3n
=5m-n