Question

  mng giải giúp mik vs ạ

Answer 1

a) \(\dfrac{3}{5}\times\dfrac{7}{9}+\dfrac{3}{5}\times\dfrac{2}{9}+\dfrac{-3}{5}\)

\(=\dfrac{3}{5}\times\dfrac{7}{9}+\dfrac{3}{5}\times\dfrac{2}{9}+\dfrac{3}{5}\times\left(-1\right)\)

\(=\dfrac{3}{5}\times\left(\dfrac{7}{9}+\dfrac{2}{9}-1\right)\)

\(=\dfrac{3}{5}\times\left(1-1\right)\)

\(=\dfrac{3}{5}\times0=0\)

b) \(\dfrac{2}{3}\cdot\dfrac{17}{13}-\dfrac{2}{3}\cdot\dfrac{4}{13}\)

\(=\dfrac{2}{3}\cdot\left(\dfrac{17}{13}-\dfrac{4}{13}\right)\)

\(=\dfrac{2}{3}\cdot1=\dfrac{2}{3}\)