Răspuns :
[tex]\dfrac{5}{8}\times(-2)+2,5 = \\ \\ =-\dfrac{5}{\not8}\times \not2+2,5 = \\ \\ = -\dfrac{5}{4}+2,5 = \\ \\ = -\dfrac{^{\big{5)}}5}{4}}+\dfrac{^{\big{2)}}25}{10} = \\ \\ = -\dfrac{5\times 5}{20}+\dfrac{2\times 25}{20}= \\ \\ = -\dfrac{25}{20}+\dfrac{50}{20} = \\ \\ =\dfrac{50}{20}-\dfrac{25}{20} = \\ \\ =\dfrac{50-25}{20} = \\ \\ ={\dfrac{25}{20}}^{\big{(5}} = \\ \\ =\dfrac{5}{4}[/tex]