a, \(\dfrac{9}{17}.\dfrac{3}{7}+\dfrac{9}{17}:\dfrac{7}{4}=\dfrac{9}{17}.\dfrac{3}{7}+\dfrac{9}{17}.\dfrac{4}{7}=\dfrac{9}{17}.\left(\dfrac{3}{7}+\dfrac{4}{7}\right)=\dfrac{9}{17}.1=\dfrac{9}{17}\)
a)\(=\dfrac{9}{17}\cdot\dfrac{3}{7}+\dfrac{9}{17}\cdot\dfrac{4}{7}=\dfrac{9}{17}\cdot\left(\dfrac{3}{7}+\dfrac{4}{7}\right)=\dfrac{9}{17}\cdot1=\dfrac{9}{17}\)
c)\(=\dfrac{6}{7}.\left(\dfrac{8}{13}+\dfrac{9}{13}-\dfrac{4}{13}\right)=\dfrac{6}{7}\cdot\dfrac{13}{13}=\dfrac{6}{7}\)
ủa sao mà thư nguỹn với chị ka là cùng một người hả
