Алгебра
Английский
Биология
География
Геометрия
История
Русский
Обществознание
Физика
Химия
Информатика
Литература
МатематикаРешебник по математике 6 класс Мерзляк ФГОС Задание 1356
Задание 1356
\[\boxed{\mathbf{1356}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ 2,5x = - 1\]
\[x = - 1\ :2,5\]
\[x = - 0,4.\]
\[Ответ:x = - 0,4.\ \]
\[2)\ 0,3x = 1\]
\[x = 1\ :0,3\]
\[x = 10\ :3\]
\[x = 3\frac{1}{3}.\]
\[Ответ:\ x = 3\frac{1}{3}.\]
\[3)\ 7x = - 3\]
\[x = - 3\ :7\]
\[x = - \frac{3}{7}.\]
\[Ответ:\ x = - \frac{3}{7}.\]
\[4) - 16x = 8\]
\[x = 8\ :( - 16)\]
\[x = - 0,5.\]
\[Ответ:\ x = - 0,5.\]
\[5)\ |x| - 5 = 0\]
\[|x| = 5\]
\[x = \pm 5.\]
\[Ответ:\ x = \pm 5.\ \]
\[6)\ |x| + 3,2 = 8\]
\[|x| = 8 - 3,2\]
\[|x| = 4,8\]
\[x = \pm 4,8.\]
\[Ответ:\ x = \pm 4,8.\ \]
\[7)\ 4,1 - |x| = 5\]
\[|x| = 4,1 - 5\]
\[|x| = - 0,9\]
\[Ответ:\ корней\ нет.\ \]
\[8)\ |3x + 1,8| = 0\]
\[3x + 1,8 = 0\]
\[3x = - 1,8\]
\[x = - 1,8\ :3\]
\[x = - 0,6.\]
\[Ответ:\ x = - 0,6.\ \]
\[9)\ 9|x| - 6 = 0\]
\[9|x| = 6\]
\[|x| = \frac{6}{9}\]
\[|x| = \frac{2}{3}\]
\[x = \pm \frac{2}{3}.\]
\[Ответ:\ x = \pm \frac{2}{3}\text{.\ }\]
\[10)\ \frac{8}{x} = \frac{6}{5}\]
\[6x = 8 \cdot 5\]
\[6x = 40\]
\[x = \frac{40}{6} = \frac{20}{3}\]
\[x = 6\frac{2}{3}.\]
\[Ответ:\ x = 6\frac{2}{3}\text{.\ }\]
\[11)\ \frac{7}{4} = \frac{x}{2}\]
\[4x = 7 \cdot 2\]
\[x = \frac{7 \cdot 2}{4}\]
\[x = \frac{7}{2}\]
\[x = 3,5.\]
\[Ответ:\ x = 3,5.\ \]
\[12)\ \frac{x + 3}{12} = \frac{4}{3}\]
\[3 \cdot (x + 3) = 12 \cdot 4\]
\[3x + 9 = 48\]
\[3x = 48 - 9\]
\[3x = 39\]
\[x = 39\ :3\]
\[x = 13.\]
\[Ответ:\ x = 13.\ \]
\[13)\ 7x = x + 25\]
\[7x - x = 25\]
\[6x = 25\]
\[x = \frac{25}{6}\]
\[x = 4\frac{1}{6}.\]
\[Ответ:\ x = 4\frac{1}{6}\text{.\ }\]
\[14)\ 0,4x - 6 = 0,6x - 9\]
\[0,6x - 0,4x = - 6 + 9\]
\[0,2x = 3\]
\[x = 3\ :0,2 = 30\ :2\]
\[x = 15.\]
\[Ответ:\ x = 15.\ \]
\[15)\ 3x + 16 = 9 - 10x\]
\[3x + 10x = 9 - 16\]
\[13x = - 7\]
\[x = - \frac{7}{13}.\]
\[Ответ:\ x = - \frac{7}{13}\text{.\ }\]
\[16)\ 0,6\left( x + 1\frac{2}{3} \right) = - 1,2\]
\[0,6x + 0,6 \cdot \frac{5}{3} = - 1,2\]
\[0,6x + 0,2 \cdot 5 = - 1,2\]
\[0,6x = - 1,2 - 1\]
\[0,6x = - 2,2\]
\[x = - 2,2\ :0,6\]
\[x = - \frac{22}{6} = - \frac{11}{3}\]
\[x = - 3\frac{2}{3}.\]
\[Ответ:\ x = - 3\frac{2}{3}\text{.\ }\]
\[17) - 3,4\left( x + 9\frac{3}{11} \right) = - 68\]
\[- 3,4x - 3,4 \cdot \frac{102}{11} = - 68\ \ \ \ | \cdot 11\]
\[- 37,4x - 3,4 \cdot 102 = - 748\]
\[- 37,4x - 346,8 = - 748\]
\[- 37,4x = - 748 + 346,8\]
\[- 37,4x = - 401,2\]
\[x = 4012\ :374\]
\[x = \frac{4012}{374} = \frac{2006}{187}\]
\[x = 10\frac{136}{187} = 10\frac{8}{11}.\]
\[Ответ:\ x = 10\frac{8}{11}\text{.\ }\]
\[18)\ \frac{x}{3} + \frac{x}{4} = - 21\ \ \ \ | \cdot 12\]
\[4x + 3x = - 252\]
\[7x = - 252\]
\[x = - 36.\]
\[Ответ:\ x = - 36.\ \]
\[19)\ \frac{2m}{3} - \frac{4m}{5} = 3\ \ \ \ \ | \cdot 15\]
\[5 \cdot 2m - 3 \cdot 4m = 45\]
\[10m - 12m = 45\]
\[- 2m = 45\]
\[m = - 45\ :2\]
\[m = - 22,5.\]
\[Ответ:\ m = - 22,5.\]
\[20)\ \frac{4a}{9} - 1 = \frac{5a}{12}\ \ \ \ \ \ \ | \cdot 36\]
\[4 \cdot 4a - 36 = 5a \cdot 3\]
\[16a - 15a = 36\]
\[a = 36.\]
\[Ответ:\ a = 36.\ \]
\[21)\ 3(1 - x) + 5(x + 2) =\]
\[= 1 - 4x\]
\[3 - 3x + 5x + 10 + 4x = 1\]
\[6x = 1 - 13\]
\[6x = - 12\]
\[x = - 2.\]
\[Ответ:\ x = - 2.\ \]
\[22)\ 3(2 - x) - (5x + 4) =\]
\[= 0,4 - 16x\]
\[6 - 3x - 5x - 4 + 16x = 0,4\]
\[8x = 0,4 + 4 - 6\]
\[8x = - 1,6\]
\[x = - 0,2.\]
\[Ответ:\ x = - 0,2.\ \]
\[23)\ 2(3 - 5p) = 4(1 - p) - 1\]
\[6 - 10p = 4 - 4p - 1\]
\[10p - 4p = 6 - 4 + 1\]
\[6p = 3\]
\[p = 3\ :6\]
\[p = 0,5.\]
\[Ответ:\ p = 0,5.\ \]
\[24)\ 0,5(2y - 1) -\]
\[- (0,5 - 0,2y) + 1 = 0\]
\[y - 0,5 - 0,5 + 0,2y + 1 = 0\]
\[1,2y = 0\]
\[y = 0.\]
\[Ответ:\ y = 0.\ \]
\[25) - 4(5 - 2m) + 3(m - 4) =\]
\[= 6(2 - m) - 5m\]
\[- 20 + 8m + 3m - 12 = 12 -\]
\[- 6m - 5m\]
\[11m + 11m = 12 + 12 + 20\]
\[22m = 44\]
\[m = 2.\]
\[Ответ:\ m = 2.\ \]
\[26)\ 0,3(3x - 1) + 0,2 =\]
\[= 5(0,1 - 0,2x) - 0,1\]
\[0,9x - 0,3 + 0,2 = 0,5 - x - 0,1\]
\[0,9x + x = 0,4 + 0,1\]
\[1,9x = 0,5\]
\[x = \frac{5}{19}.\]
\[Ответ:\ x = \frac{5}{19}\text{.\ }\]
