Question

Tìm x biết :

a) -2/5+5/6x=-4/15                                     b) 2/3+7/4:x=5/6

 

Answer 1

a) \(-\dfrac{2}{5}+\dfrac{5}{6}x=-\dfrac{4}{15}\\ \Leftrightarrow\dfrac{5}{6}x=\dfrac{2}{15}\\ \Leftrightarrow x=\dfrac{4}{25}\)

b) \(\dfrac{2}{3}+\dfrac{7}{4}\div x=\dfrac{5}{6}\\ \Leftrightarrow\dfrac{7}{4}\div x=\dfrac{1}{6}\\ \Leftrightarrow x=\dfrac{7}{24}\)

Answer 2

a: Ta có: \(-\dfrac{2}{5}+\dfrac{5}{6}x=\dfrac{-4}{15}\)

\(\Leftrightarrow x\cdot\dfrac{5}{6}=\dfrac{2}{15}\)

hay \(x=\dfrac{4}{25}\)

b: Ta có: \(\dfrac{7}{4}:x+\dfrac{2}{3}=\dfrac{5}{6}\)

\(\Leftrightarrow\dfrac{7}{4}:x=\dfrac{1}{6}\)

hay \(x=\dfrac{21}{2}\)