d) $\dfrac{x}{10}$ = $\dfrac{12}{5}$

  ` x . 5 = 12 . 10 `

  ` 5x = 120 `

  ` x = 120 : 5 `

  ` x = 24 `

e) $\dfrac{x}{28}$ = $\dfrac{-4}{7}$

  ` x . 7 = ( -4 ) . 28 `

  ` 7x = -112 `

  ` x = -112 : 7 `

  ` x = -16 `

f) ` 2`$\dfrac{2}{3}$ ` : x = 1 ` $\dfrac{7}{9}$ ` : 0,02 `

    $\dfrac{8}{3}$ ` : x = ` $\dfrac{16}{9}$ ` . 50 `

    $\dfrac{8}{3}$ ` : x = ` $\dfrac{800}{9}$

    ` x = ` $\dfrac{8}{3}$ : $\dfrac{800}{9}$

    ` x = ` $\dfrac{3}{100}$

g) ` | x + 5 | - 6 = 9 `

    ` | x + 5 | = 9 + 6 `

    ` | x + 5 | = 15 `

    $\left[\begin{matrix} x + 5 = 15 \\ x + 5 = -15 \end{matrix}\right.$

    $\left[\begin{matrix} x = 10 \\ x = -20 \end{matrix}\right.$

h) ` | x - ` $\dfrac{2}{5}$ ` | + 3/4 = 11/4 `

    ` | x - ` $\dfrac{2}{5}$ ` | = 11/4 - 3/4 `

    ` | x - ` $\dfrac{2}{5}$ ` | = 2 `

    $\left[\begin{matrix} x - \dfrac{2}{5} = 2 \\ x - \dfrac{2}{5} = -2 \end{matrix}\right.$

      $\left[\begin{matrix} x = \dfrac{12}{5} \\ x = \dfrac{-8}{5} \end{matrix}\right.$

i) ` | x + ` $\dfrac{4}{5}$ ` | - ` $\dfrac{2}{5}$ ` = 3/5 `

   ` | x + 4/5 | = 3/5 + 2/5 `

   ` | x + 4/5 | = 1 `

  $\left[\begin{matrix} x + \dfrac{4}{5} = 1 \\ x + \dfrac{4}{5} = -1 \end{matrix}\right.$

  $\left[\begin{matrix} x = \dfrac{1}{5} \\ x = \dfrac{-9}{5}  \end{matrix}\right.$

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