tìm x: X - 4/5=2/3:1/4 X x 4/7=5/2-1

$\textit{1. }$

$\text{x - $\dfrac{4}{5}$ = $\dfrac{2}{3}$ : $\dfrac{1}{4}$}$

$\text{x - $\dfrac{4}{5}$ = $\dfrac{2}{3}$ x 4}$

$\text{x - $\dfrac{4}{5}$ = $\dfrac{8}{3}$}$

$\text{x = $\dfrac{4}{5}$ + $\dfrac{8}{3}$}$

$\text{x = $\dfrac{12}{15}$ + $\dfrac{40}{15}$}$

$\text{x = $\dfrac{52}{15}$ }$

$\text{Vậy x = $\dfrac{52}{15}$ }$

$\textit{2. }$

$\textit{x}$ $\text{x $\dfrac{4}{7}$ = $\dfrac{5}{2}$ - 1}$

$\textit{x}$ $\text{x $\dfrac{4}{7}$ = $\dfrac{5}{2}$ - $\dfrac{2}{2}$}$

$\textit{x}$ $\text{x $\dfrac{4}{7}$ = $\dfrac{3}{2}$}$

$\textit{x}$ $\text{= $\dfrac{3}{2}$ : $\dfrac{4}{7}$}$

$\textit{x}$ $\text{= $\dfrac{3}{2}$ x $\dfrac{7}{4}$}$

$\textit{x}$ $\text{= $\dfrac{21}{8}$}$

$\text{Vậy}$ $\textit{x}$ $\text{= $\dfrac{21}{8}$}$

$\textit{@thaotrang2910}$

$\textit{Hoidap247}$