\[(6.2-y)\cdot5.6=28;\]
\[6.2-y=28:5.6=5;\]
\[-y=5-6.2=-1.2;\]
\[y=1.2.\]
Проверка: \((6.2-1.2)\cdot5.6=5\cdot5.6=28\).
Ответ: у = 1,2.