Решебник по алгебре 7 класс Мерзляк Задание 48

\[\boxed{\text{48\ (48).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

Пояснение.

Решение.

\[1)\ \frac{7x^{\backslash 3}}{6} - \frac{5x}{18} = \frac{4}{27}\]

\[\frac{21x - 5x}{18} = \frac{4}{27}\]

\[\frac{16x}{18} = \frac{4}{27}\]

\[27 \cdot 16x = 4 \cdot 18\]

\[x = \frac{4 \cdot 18}{27 \cdot 16}\]

\[x = \frac{1}{6}\]

\[Ответ:x = \frac{1}{6}.\]

\[2)\ \frac{2x^{\backslash 4}}{7} + \frac{x^{\backslash 7}}{4} = \frac{15}{14}\]

\[\frac{8x + 7x}{28} = \frac{15}{14}\]

\[\frac{15x}{28} = \frac{15}{14}\]

\[15x \cdot 14 = 28 \cdot 15\]

\[x = \frac{15 \cdot 28}{15 \cdot 14}\]

\[x = 2\]

\[Ответ:x = 2.\]

\[3) - \frac{x}{8} + 1 = \frac{x}{12}\]

\[\frac{x^{\backslash 2}}{12} + \frac{x^{\backslash 3}}{8} = 1\]

\[\frac{2x + 3x}{24} = 1\]

\[\frac{5x}{24} = 1\]

\[5x = 24\]

\[x = \frac{24}{5}\]

\[x = 4\frac{4}{5} = 4,8\]

\[Ответ:x = 4,8.\ \]