5/14 у -12 = 4/21 у - 7,5

3,8-у/5,5=3,6-у/11

5/14 у -12 = 4/21 у - 7,55/14y-4/21y=12-7,57/42y=4,5y=45/10*6/1y=27================3,8-у/5,5=3,6-у/11-y/5,5+y/11=3,6-3,8-y/11=-0,2-y=-0,2*11y=2,2