\(a,\dfrac{5\left(x-1\right)+2}{6}-\dfrac{7x-1}{4}=\dfrac{2\left(2x+1\right)}{7}-5\)
\(\Leftrightarrow\dfrac{5x-5+2}{6}-\dfrac{7x-1}{4}=\dfrac{4x+2}{7}-5\)
\(\Leftrightarrow\dfrac{5x-3}{6}-\dfrac{7x-1}{4}=\dfrac{4x+2}{7}-5\)
\(\Leftrightarrow\dfrac{14\left(5x-3\right)}{84}-\dfrac{21\left(7x-1\right)}{84}=\dfrac{12\left(4x+2\right)}{84}-\dfrac{420}{84}\)
\(\Leftrightarrow14\left(5x-3\right)-21\left(7x-1\right)=12\left(4x+2\right)-420\)
\(\Leftrightarrow70x-42-147x+21-48x-24+420=0\)
\(\Leftrightarrow-125x+375=0\)
\(\Leftrightarrow-125x=-375\)
\(\Leftrightarrow x=3\)
Đúng 1
Bình luận (0)
