Решебник по математике 6 класс Мерзляк ФГОС Задание 1158

\[\boxed{\mathbf{1158\ (1150)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]

\[1)\ 0,4 \cdot (x - 3) - 1,6 =\]

\[= 5 \cdot (0,1x - 0,5)\]

\[0,4x - 1,2 - 1,6 = 0,5x - 2,5\]

\[0,5x - 0,4x = - 2,8 + 2,5\]

\[0,1x = - 0,3\]

\[x = - 3\]

\[Ответ:\ - 3.\]

\[2)\ 1,5 \cdot (2x - 5) + 2x =\]

\[= 5 \cdot (0,5x - 1,5) - 10\]

\[3x - 7,5 + 2x = 2,5x - 7,5 - 10\]

\[5x - 2,5x = - 17,5 + 7,5\]

\[2,5x = - 10\]

\[x = - 4\]

\[Ответ:\ - 4.\]

\[3)\frac{2}{3} \cdot \left( 1\frac{1}{2}x + \frac{3}{5} \right) -\]

\[- \frac{4}{5} \cdot \left( \frac{5}{12}x - \frac{1}{2} \right) = 1\frac{3}{5}\]

\[x + \frac{2}{5} - \frac{1}{3}x + \frac{2}{5} = 1\frac{3}{5}\]

\[\frac{2}{3}x + \frac{4}{5} = \frac{8}{5}\]

\[\frac{2}{3}x = \frac{8}{5} - \frac{4}{5}\]

\[\frac{2}{3}x = \frac{4}{5}\]

\[x = \frac{4 \cdot 3}{5 \cdot 2} = \frac{6}{5}\]

\[x = 1,2\]

\[Ответ:1,2.\]