Question

Tìm x :

1 / 3 x + 5 / 3 x + x = - 5 / 7

Answer 1

\(\Rightarrow\dfrac{1}{3}x+\dfrac{5}{3}x+1x=\dfrac{-5}{7}\\ x\cdot\left(\dfrac{1}{3}+\dfrac{5}{3}+1\right)=\dfrac{-5}{7}\\ x\cdot3=\dfrac{-5}{7}\\ x=\dfrac{-5}{21}\)

Answer 2

\(\dfrac{1}{3}x+\dfrac{5}{3}x+x=-\dfrac{5}{7}\)

\(\left(\dfrac{1}{3}+\dfrac{5}{3}+1\right)x=-\dfrac{5}{7}\)

\(\left(\dfrac{1}{3}+\dfrac{5}{3}+\dfrac{3}{3}\right)x=-\dfrac{5}{7}\)

\(3x=-\dfrac{5}{7}\)

\(\Rightarrow x=-\dfrac{5}{7}:3\)

\(\Rightarrow x=-\dfrac{5}{7}.\dfrac{1}{3}\)

\(\Rightarrow x=-\dfrac{5}{21}\)