Bonjour,
[tex]a = \frac{16}{7} - 7 + \frac{9}{14} [/tex]
[tex]a = \frac{16}{7} - \frac{7 \times 7}{1 \times 7} + \frac{9}{14} [/tex]
[tex]a = \frac{16}{7} - \frac{7}{7} + \frac{9}{14} [/tex]
[tex]a = \frac{16 - 7}{7} + \frac{9}{14} [/tex]
[tex]a = \frac{9}{7} + \frac{9}{14} [/tex]
[tex]a = \frac{9 \times 2}{7 \times 2} + \frac{9}{14} [/tex]
[tex]a = \frac{18}{14} + \frac{9}{14} [/tex]
[tex]a = \frac{18 + 9}{14} [/tex]
[tex]a = \frac{27}{14} [/tex]
Bonne journée !