Đáp án:
$\dfrac{-1273}{1053}$
Giải thích các bước giải:
$c)\dfrac{-5}{9}.\dfrac{2}{13}+\dfrac{-5}{9}.\dfrac{11}{9}-\dfrac{4}{9}\\
=\dfrac{-5}{9}.\left ( \dfrac{2}{13}+\dfrac{11}{9} \right )-\dfrac{4}{9}\\
=\dfrac{-5}{9}.\left ( \dfrac{2.9}{117}+\dfrac{11.13}{117} \right )-\dfrac{4}{9}\\
=\dfrac{-5}{9}.\dfrac{161}{117}-\dfrac{4}{9}\\
=\dfrac{-1}{9}.\left ( \dfrac{805}{117}+4 \right )\\
=\dfrac{-1}{9}.\left ( \dfrac{805}{117}+\dfrac{4.117}{117} \right )\\
=\dfrac{-1}{9}.\dfrac{1273}{117}\\
=\dfrac{-1273}{1053}$
