Respuesta :

kittymaniac
[tex]\frac{a}{7} + \frac{5}{7} = \frac{2}{7} \\ \frac{a + 5}{7} = \frac{2}{7} \\ 7(\frac{a + 5}{7}) = 7(\frac{2}{7})[/tex]
a + 5 = 2
a + 5 - 5 = 2 - 5
a = -3

Hope this helps! :)