Tìm x, biết 2.5 x + 3/2 = 3/5 - (-1/4)

\[\frac{2}{5}\]x + \[\frac{3}{2}\] = \[\frac{3}{5} - \left( { - \frac{1}{4}} \right)\] hay \[\frac{2}{5}\]x = \[\frac{3}{5} - \left( { - \frac{1}{4}} \right) - \frac{3}{2}\]= \[\frac{{ - 13}}{{20}}\].

Suy ra x = \[ - \frac{{13}}{{20}}:\frac{2}{5}\] = \[ - \frac{{13}}{8}\].