Explicație pas cu pas:
[tex] - \frac{2}{7} - ( - \frac{5}{7} ) = - \frac{2}{7} + \frac{5}{7} = \frac{ - 2 + 5}{7} = \frac{3}{7} [/tex]
[tex] - \frac{4}{3} - ( + \frac{70}{3} ) = - \frac{4}{3} - \frac{70}{3} = \frac{ - 4 - 70}{3} = - \frac{74}{3} [/tex]
[tex] \frac{9}{4} - ( - \frac{3}{4} ) = \frac{9}{4} + \frac{3}{4} = \frac{9 + 3}{4} = \frac{12}{4} = 3[/tex]
[tex] + \frac{1}{3} - ( + \frac{1}{6} ) = \frac{1}{3} - \frac{1}{6}=\frac{2}{6} - \frac{1}{6} = \frac{2 - 1}{6} = \frac{1}{6} [/tex]
[tex] - \frac{2}{5} - ( - \frac{7}{10} ) = - \frac{2}{5} + \frac{7}{10} = - \frac{4}{10} + \frac{7}{10} = \frac{ - 4 + 7}{10} = \frac{3}{10}[/tex]
[tex]\frac{5}{12} - ( - \frac{1}{6} ) = \frac{5}{12} + \frac{1}{6} = \frac{5}{12} + \frac{2}{12} = \frac{5 + 2}{12} = \frac{7}{12} [/tex]
[tex] - \frac{1}{24} - ( + \frac{9}{8} ) = - \frac{1}{24} - \frac{9}{8} = - \frac{1}{24} - \frac{27}{24} = \frac{ - 1 - 27}{24} = - \frac{28}{24} = - \frac{7}{6} [/tex]
[tex]4.5 - (4.5 - 3) = 4.5 - 1.5 = 3[/tex]
[tex] - 7.7 - ( - 2.8) - 9 = - 7.7 + 2.8 - 9 = 2.8 - (7.7 + 9) = 2.8 - 16.7 = - 13.9[/tex]
