x-(25%)^2x=`1/2`-1`3/4` (1,4x-6):`2/3`=-3-1`1/5`

x – (25%)² . x = $\frac{1}{2}$ – 1$\frac{3}{4}$ 

x – ($\frac{1}{4}$)² . x = $\frac{1}{2}$ – $\frac{7}{4}$

x – $\frac{1}{16}$ . x = $\frac{4}{8}$ – $\frac{14}{8}$

x . (1 – $\frac{1}{16}$) = $\frac{-5}{4}$

x . $\frac{15}{16}$ = $\frac{-5}{4}$

x = $\frac{-5}{4}$ : $\frac{15}{16}$

x = $\frac{-4}{3}$

Vậy x = $\frac{-4}{3}$

(1,4 . x – 6) : $\frac{2}{3}$ = -3 – 1$\frac{1}{5}$

($\frac{7}{5}$ . x – 6) : $\frac{2}{3}$ = -3 – $\frac{6}{5}$

($\frac{7}{5}$ . x – 6) : $\frac{2}{3}$ = $\frac{-21}{5}$

$\frac{7}{5}$ . x – 6 = $\frac{-21}{5}$ . $\frac{2}{3}$ 

$\frac{7}{5}$ . x – 6 = $\frac{-14}{5}$

$\frac{7}{5}$ . x = $\frac{-14}{5}$ + 6

$\frac{7}{5}$ . x = $\frac{16}{5}$

x = $\frac{16}{5}$ : $\frac{7}{5}$

x = $\frac{16}{7}$

Vậy x = $\frac{16}{7}$