-(5a-4b)+2(a-2b)=?

问题描述:

-(5a-4b)+2(a-2b)=?

-(5a-4b)+2(a-2b)
=-5a+4b+2a-4b
=-5a+2a
=-3a

-(5a-4b)+2(a-2b)
=-5a+4b+2a-4b
=-3a