1,6 x - 20%x + x = -1 $\frac{1}{5}$
=> $\frac{8}{5}$ x - $\frac{1}{5}$ x + x = - $\frac{-6}{5}$
=> ( $\frac{8}{5}$ - $\frac{1}{5}$ + 1) x = - $\frac{-6}{5}$
=> ( $\frac{8}{5}$ - $\frac{1}{5}$ + $\frac{5}{5}$ ) x = - $\frac{-6}{5}$
=> $\frac{8 - 1 + 5}{5}$ x = - $\frac{-6}{5}$
=> $\frac{12}{5}$ x = - $\frac{-6}{5}$
=> x = - $\frac{-6}{5}$ : $\frac{12}{5}$
=> x = -$\frac{1}{2}$
Vậy x = -$\frac{1}{2}$
