Đáp án:
1. $\dfrac{2}{3} + \dfrac{1}{3}x = \dfrac{1}{2}x - 1$
$\dfrac{1}{3}x - \dfrac{1}{2}x = - 1 - \dfrac{2}{3}$
$- \dfrac{1}{6}x = - \dfrac{5}{3}$
$x = - \dfrac{5}{3} : (- \dfrac{1}{6})$
$x = 10$
2. $|\dfrac{5}{18}| - x - \dfrac{1}{4} = \dfrac{3}{8}$
$\dfrac{5}{18} - x - \dfrac{1}{4} = \dfrac{3}{8}$
$- x = \dfrac{3}{8} - \dfrac{5}{18} + \dfrac{1}{4}$
$- x = \dfrac{25}{72}$
$x = - \dfrac{25}{72}$
3. $\dfrac{3}{2}|\dfrac{1}{3} - x| + \dfrac{1}{3} = 4$
$\dfrac{3}{2}|\dfrac{1}{3} - x| = 4 - \dfrac{1}{3}$
$\dfrac{3}{2}|\dfrac{1}{3} - x| = \dfrac{11}{3}$
$|\dfrac{1}{3} - x| = \dfrac{11}{3} : \dfrac{1}{3}$
$|\dfrac{1}{3} - x| = 11$
Suy ra:
*) $\dfrac{1}{3} - x = 11 \to x = \dfrac{1}{3} - 11$
$x = - \dfrac{32}{3}$
*) $\dfrac{1}{3} - x = - 11 \to x = 11 + \dfrac{1}{3}$
$x = \dfrac{34}{3}$
4. $\dfrac{x}{3} = 2$
$x.\dfrac{1}{3} = 2$
$x = 2 : \dfrac{1}{3}$
$x = 6$
Giải thích các bước giải:
