Answer 1

\[(\frac{- 4}{3} \times \frac{12}{- 5}) + (\frac{3}{7} \times \frac{21}{15})\]
\[ = \frac{4 \times 4}{5} + \frac{1 \times 3}{5}\]
\[ = \frac{16}{5} + \frac{3}{5}\]
\[ = \frac{16 + 3}{5}\]
\[ = \frac{19}{5}\]