$\textit{Đáp án + Giải thích các bước giải:}$
$\text{b) $\dfrac{3}{7}$$x^{}$ - 0,4 = $\dfrac{-17}{35}$}$
$\text{$\dfrac{3}{7}$$x^{}$ - $\dfrac{14}{35}$ = $\dfrac{-17}{35}$}$
$\text{$\dfrac{3}{7}$$x^{}$ = $\dfrac{-17}{35}$ + $\dfrac{14}{35}$ = $\dfrac{-3}{35}$}$
$\text{$x^{}$ = $\dfrac{-3}{35}$ : $\dfrac{3}{7}$ = $\dfrac{-3}{35}$ . $\dfrac{7}{3}$}$
$\text{$x^{}$ = $\dfrac{-1}{5}$}$
$\text{c) 0,2($x^{}$ - 3) + 2,4 = 10}$
$\text{$x^{}$ - 3 = (10 - 2,4) : 0,2 38}$
$\text{$x^{}$ = 38 + 3}$
$\text{$x^{}$ = 41}$
