4/7(2,7m-2 1/4a)-4,2(5/7m-0.5a)помогите
4/7*2,7m-4/7*2 1/4a-4,2*5/7m+4,2*0,5a=54/35m-9/7a-3m+2,1a=57/70a-1 16/35m