$\text{7) $\dfrac{2}{3}$x - $\dfrac{3}{2}$x = $\dfrac{5}{12}$}$

$\text{x($\dfrac{2}{3}$ - $\dfrac{3}{2}$) = $\dfrac{5}{12}$}$

$\text{x($\dfrac{4}{6}$ - $\dfrac{9}{6}$) = $\dfrac{5}{12}$}$

$\text{-$\dfrac{5}{6}$x = $\dfrac{5}{12}$}$

$\text{x = $\dfrac{5}{12}$ : (-$\dfrac{5}{6}$)}$

$\text{x = $\dfrac{5}{12}$ . (-$\dfrac{6}{5}$)}$

$\text{x = -$\dfrac{1}{2}$}$

$\text{Vậy x = -$\dfrac{1}{2}$}$

$\text{8) $\dfrac{7}{9}$ : (2 + $\dfrac{3}{4}$x) + $\dfrac{5}{9}$ = $\dfrac{23}{27}$}$

$\text{$\dfrac{7}{9}$ : (2 + $\dfrac{3}{4}$x) = $\dfrac{23}{27}$ - $\dfrac{5}{9}$}$

$\text{$\dfrac{7}{9}$ : (2 + $\dfrac{3}{4}$x) = $\dfrac{23}{27}$ - $\dfrac{15}{27}$}$

$\text{$\dfrac{7}{9}$ : (2 + $\dfrac{3}{4}$x) = $\dfrac{8}{27}$}$

$\text{2 + $\dfrac{3}{4}$x = $\dfrac{7}{9}$ : $\dfrac{8}{27}$}$

$\text{2 + $\dfrac{3}{4}$x = $\dfrac{7}{9}$ . $\dfrac{27}{8}$}$

$\text{2 + $\dfrac{3}{4}$x = $\dfrac{21}{8}$}$

$\text{$\dfrac{3}{4}$x = $\dfrac{21}{8}$ - 2}$

$\text{$\dfrac{3}{4}$x = $\dfrac{21}{8}$ - $\dfrac{16}{8}$}$

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

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

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

$\text{x = $\dfrac{5}{6}$}$

$\text{Vậy x = $\dfrac{5}{6}$}$

$\textit{Ha1zzz}$

`7) 2/3x - 3/2x = 5/12`

`( 2/3 - 3/2)x = 5/12`

`(4/6 - 9/6) x = 5/12`

`-5/6 x = 5/12`

`x = 5/12 : (-5)/6`

`x = -1/2`

Vậy `x = -1/2`

``

`8) 7/9 : ( 2 + 3/4x) + 5/9 = 23/27`

`7/9 : ( 2 + 3/4x)= 23/27 - 5/9`

`7/9 : ( 2 + 3/4x) =  23/27 - 15/27`

`7/9 : ( 2 + 3/4x) =8/27`

`( 2 + 3/4x) = 7/9 : 8/27`

`2 + 3/4x= 21/8`

`3/4x = 21/8 - 2`

`3/4x = 21/8 - 16/8`

`3/4x = 5/8`

`x = 5/8 : 3/4`

`x= 5/6`

 Vậy `x = 5/6`

`#caty09`