Question

Tìm X:1/2+3/5.(X-2)=20%

 

Answer 1

\(\dfrac{1}{2}+\dfrac{3}{5}\left(x-2\right)=20\%\\ \Leftrightarrow\dfrac{1}{2}+\dfrac{3}{5}\left(x-2\right)=\dfrac{1}{5}\\ \Leftrightarrow\dfrac{3}{5}\left(x-2\right)=-\dfrac{3}{10}\\ \Leftrightarrow x-2=-\dfrac{1}{2}\\ \Leftrightarrow x=2-\dfrac{1}{2}\\ \Leftrightarrow x=\dfrac{3}{2}\)

Answer 2

1/2+3/5.(X-2)=20%

1/2+3/5.(X-2)=1/5

 3/5.(X-2)=1/5-1/2

3/5.(X-2)=2/10-5/10

3/5.(X-2)=-3/10

x-2=-3/10:3/5

x-2=-3/10.5/3

x-2=-1/2

x=-1/2+2

x=3/2