(у+1,05)*20,1=209,04
(y+1,05)*20,1=209,04 y+1,05=209,04:20,1 y+1,05=10,4 y=10,4-1,05 y=9,35 Проверка (9,35+1,05)*20,1=209,04 1)9,35+1,05=10,4 2)10,4*20,1=209,04
Y+1.05= 209.04:20.1=10.4 y= 10.4-1.05= 9.35