Hello
To solve this problem, we should add the fractions together.
[tex]-\frac{5}{7}+\frac{2}{3}[/tex]Find the LCM between 7 and 3 and that would be 21
[tex]\begin{gathered} -\frac{5}{7}+\frac{2}{3} \\ \frac{-3(5)+7(2)}{21}=\frac{-15+14}{21}=-\frac{1}{21} \end{gathered}[/tex]From the calculations above, the answer is -1/21