Giải thích các bước giải:
a)$\dfrac{3}{5}$x+$\dfrac{2}{3}$=$\dfrac{4}{5}$
$\dfrac{3}{5}$x=$\dfrac{4}{5}$-$\dfrac{2}{3}$
$\dfrac{3}{5}$x=$\dfrac{12}{15}$-$\dfrac{10}{15}$
$\dfrac{3}{5}$x=$\dfrac{2}{15}$
x=$\dfrac{2}{15}$:$\dfrac{3}{5}$
x=$\dfrac{2}{15}$.$\dfrac{5}{3}$
⇒ x= $\dfrac{2}{9}$
b)|$\dfrac{1}{2}$x+$\dfrac{3}{5}$|= $\dfrac{1}{2}$
$\dfrac{1}{2}$x+$\dfrac{3}{5}$=$\dfrac{1}{2}$ hoặc $\dfrac{1}{2}$x+$\dfrac{3}{5}$=-$\dfrac{1}{2}$
$\dfrac{1}{2}$x= $\dfrac{1}{2}$- $\dfrac{3}{5}$ hoặc $\dfrac{1}{2}$x=-$\dfrac{1}{2}$-$\dfrac{3}{5}$
$\dfrac{1}{2}$x= -$\dfrac{1}{10}$ hoặc $\dfrac{1}{2}$x= -$\dfrac{11}{10}$
x=-$\dfrac{1}{10}$:$\dfrac{1}{2}$ hoặc x=-$\dfrac{11}{10}$:$\dfrac{1}{2}$
x=-$\dfrac{1}{5}$ hoặc x=-$\dfrac{11}{5}$
