Решебник по алгебре 7 класс Мерзляк Задание 47

\[\boxed{\text{47\ (47).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

Пояснение.

Решение.

\[1)\ \frac{2x}{3} + \frac{5x}{4} = 23\ \ \ \ | \cdot 12\]

\[\frac{8x + 15x}{12} = 23 \cdot 12\]

\[23x = 23 \cdot 12\]

\[x = 12\]

\[Ответ:x = 12.\]

\[2)\ \frac{x^{\backslash 4}}{6} - \frac{x^{\backslash 3}}{8} = \frac{7}{36}\text{\ \ \ \ \ \ \ }\]

\[\frac{4x - 3x}{24} = \frac{7}{36}\]

\[\frac{x}{24} = \frac{7}{36}\]

\[x = \frac{7}{36} \cdot 24\]

\[x = \frac{7 \cdot 24}{36}\]

\[x = \frac{14}{3}\]

\[x = 4\frac{2}{3}\]

\[Ответ:x = 4\frac{2}{3}.\]

\[3)\ \frac{3x}{10} - \frac{4}{15} = \frac{x}{6}\ \ \ \ \ \ \ \ | \cdot 30\]

\[9x - 8 = 5x\]

\[9x - 5x = 8\]

\[4x = 8\]

\[x = 8\ :2\]

\[x = 2\]

\[Ответ:x = 2.\]