[у - 8,12/19]+1,7/19= 6,2/9
(у - 8 12/19)+1 7/19= 6 2/9
у- 8 12/19=6 2/9- 1 7/19
у-164/19=56/9- 26/19
у-164/19=1064/171- 234/171
у-164/19=830/171
у=830/171+164/19
у=830/171+1476/19
у=2306/171= 13 83/171
(у-8 12/19)+1 7/19=6 2/9
у- 8 12/19=6 2/9-1 7/19
у-8 12/19=4 146/171
у=4 146/171+8 12/19
у=13 83/171