Respuesta :

[tex] \frac{2}{3} + ( - \frac{5}{7} ) \\ = \frac{2 \times 7 - 5 \times 3}{21} \\ = \frac{14 - 15}{21} \\ = \frac{ - 1}{21} [/tex]

Answer:

[tex] \frac{ - 1}{21} [/tex]

Hope you could understand.

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