4. Решите уравнение: a) 6- 8Y+12=3

а)

Решаем уравнение:

\[6\frac{7}{8} - \frac{1}{y+\frac{1}{12}} = 3\frac{5}{6}\]

\[\frac{1}{y+\frac{1}{12}} = 6\frac{7}{8} - 3\frac{5}{6}\]

\[\frac{1}{y+\frac{1}{12}} = \frac{55}{8} - \frac{23}{6}\]

\[\frac{1}{y+\frac{1}{12}} = \frac{55 \cdot 3 - 23 \cdot 4}{24} = \frac{165 - 92}{24} = \frac{73}{24}\]

\[y+\frac{1}{12} = \frac{24}{73}\]

\[y = \frac{24}{73} - \frac{1}{12} = \frac{24 \cdot 12 - 73}{73 \cdot 12} = \frac{288 - 73}{876} = \frac{215}{876}\]

Ответ: \[y = \frac{215}{876}\]