Question

Tìm x

a) \(\dfrac{3x-5}{\dfrac{2}{\dfrac{3}{4}}}=\dfrac{4}{5}\)

b) \(\dfrac{1-\dfrac{1}{3}+\dfrac{x}{1-\dfrac{1}{3}}}{1+\dfrac{1}{3}-\dfrac{1}{1+\dfrac{1}{3}}}\)

Answer 1

a, \(\dfrac{3x-5}{\dfrac{2}{\dfrac{3}{4}}}=\dfrac{4}{5}\)

<=>(3x - 5) : \(\dfrac{2}{3}\): 4 = \(\dfrac{4}{5}\)

(3x - 5) : \(\dfrac{2}{3}\) . \(\dfrac{1}{4}\)= \(\dfrac{4}{5}\)

(3x - 5) : \(\dfrac{2}{12}\) = \(\dfrac{4}{5}\)

(3x - 5) : \(\dfrac{1}{6}\) = \(\dfrac{4}{5}\)

(3x - 5) = \(\dfrac{4}{5}\) . \(\dfrac{1}{6}\)

(3x - 5) = \(\dfrac{2.1}{5.3}=\dfrac{2}{15}\)

3x = \(\dfrac{2+75}{15}\)= \(\dfrac{77}{15}\)

x = \(\dfrac{77}{15}\). \(\dfrac{1}{3}\) = \(\dfrac{77}{45}\)