Question

\(\dfrac{1}{2}.x+\dfrac{3}{5}.\left(x-2\right)=3\)

các bạn giúp mình vs nha !

Answer 1

\(\dfrac{1}{2}x+\dfrac{3}{5}\left(x-2\right)=3\)

<=> \(\dfrac{1}{2}x+\dfrac{3}{5}x-\dfrac{6}{5}=3 \)

<=>\(\dfrac{11}{10}x=\dfrac{21}{5}\)

<=>\(x=\dfrac{42}{11}\)

Answer 2

\(\dfrac{1}{2}.x+\dfrac{3}{5}.\left(x-2\right)=3\)

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

\(\dfrac{1}{2}.x+\dfrac{3}{5}.x-\dfrac{6}{5}=3\)

\(\dfrac{1}{2}.x+\dfrac{3}{5}.x=3+\dfrac{6}{5}\)

\(\dfrac{1}{2}.x+\dfrac{3}{5}.x=\dfrac{21}{5}\)

\(x.\left(\dfrac{1}{2}+\dfrac{3}{5}\right)=\dfrac{21}{5}\)

\(x.\dfrac{11}{10}=\dfrac{21}{5}\)

\(x=\dfrac{21}{5}:\dfrac{11}{10}\)

\(x=\dfrac{42}{11}\)