Đáp án:
Giải thích các bước giải:
a) l 2x - 3.6 l - 1.4 = 0
<=>l 2x - 3.6 l -1 = 0
<=>l 2x - 3.6 l=1
<=>\(\left[ \begin{array}{l}2x-3.6=-1\\2x-3.6=1\end{array} \right.\)
<=>\(\left[ \begin{array}{l}2x-3=\frac{-1}{6}\\2x-3=\frac{1}{6}\end{array} \right.\)
<=>\(\left[ \begin{array}{l}2x=\frac{17}{6}\\2x=\frac{19}{6}\end{array} \right.\)
<=>\(\left[ \begin{array}{l}x=\frac{17}{12}\\x=\frac{19}{12}\end{array} \right.\)
b)
<=>$\frac{3}{10}$ - x : $\frac{10}{3}$ = $\frac{6}{15}$
<=>$\frac{3}{10}$=$\frac{3}{25}$
<=>x=$\frac{2}{5}$
c)
<=>x-$\frac{1}{2}$=$\frac{2}{3}$
<=>x=$\frac{7}{6}$
