Question

Tính nhanh nếu có thể:

-5/7x2/11-5/11x9/7-2/5/7

Giúp mình với!!!Khẩn cấp đấy!!!

Answer 1

\(\dfrac{-5}{7}.\dfrac{2}{11}-\dfrac{5}{11}.\dfrac{9}{7}-2\dfrac{5}{7}\)

\(=\dfrac{-2}{7}.\dfrac{5}{11}-\dfrac{5}{11}.\dfrac{9}{7}-\dfrac{19}{7}\)

\(=\dfrac{5}{11}.\left(\dfrac{-2}{7}-\dfrac{9}{7}\right)-\dfrac{19}{7}\)

\(=\dfrac{5}{11}.\dfrac{-11}{7}-\dfrac{19}{7}\)

\(=\dfrac{-5}{7}-\dfrac{19}{7}\)

\(=\dfrac{-24}{7}\)

Answer 2

\(\dfrac{-5}{7}.\dfrac{2}{11}-\dfrac{5}{11}.\dfrac{9}{7}-2\dfrac{5}{7}\)

\(=\dfrac{-2}{7}.\dfrac{5}{11}-\dfrac{5}{11}.\dfrac{9}{7}-\dfrac{19}{7}\)

\(=\dfrac{5}{7}\left(\dfrac{-2}{7}-\dfrac{9}{7}\right)-\dfrac{19}{7}\)

\(=\dfrac{5}{7}.\dfrac{-11}{7}-\dfrac{19}{7}\)

\(=\dfrac{5.\left(-11\right)}{11.7}-\dfrac{19}{7}\)

\(=\dfrac{-5.11}{11.7}-\dfrac{19}{7}\)

\(=\dfrac{-5}{7}-\dfrac{19}{7}\)

\(=\dfrac{-5-19}{7}\)

\(=\dfrac{\left(-5\right)+\left(-19\right)}{7}\)

\(=\dfrac{-24}{7}\)

Answer 3

\(\dfrac{-5}{7}\times\dfrac{2}{11}-\dfrac{5}{11}\times\dfrac{9}{7}\)\(-2\dfrac{5}{7}\)

=\(\dfrac{-5}{7}\times\dfrac{2}{11}-\dfrac{5}{11}\times\dfrac{9}{7}-\dfrac{19}{7}\)

=\(\left(\dfrac{-5}{7}\times\dfrac{2}{11}\right)+\left(\dfrac{-5}{11}\times\dfrac{9}{7}\right)-\dfrac{19}{7}\)

=\(\dfrac{-10}{77}-\dfrac{45}{77}-\dfrac{19}{7}\)

=\(\dfrac{-5}{7}-\dfrac{19}{7}\)

=\(\dfrac{-24}{7}\) hay =\(-3\dfrac{3}{7}\)