2m-3≤5
2m≤8
m≤4
1+2+3+4= 10
3 1/5 - (4 1/5Х +Х) :5 4/7=0
-(5 1/5Х) :5 4/7 = -3 1/5
-(5 1/5)Х = -3 1/5 х 5 4/7 = -16/5 х 39/7
-26/5Х = -624/35
Х = -624/35 :(-26/5) =-624/35 х (-5/26)
Х = 24/7 = 3 3/7