a.
\(\dfrac{x-1}{3}+2=5\)
\(\Leftrightarrow\dfrac{x-1}{3}+\dfrac{6}{3}=\dfrac{15}{3}\)
\(\Leftrightarrow x-1+6=15\)
\(\Leftrightarrow x-1+6-15=0\)
\(\Leftrightarrow x-10=0\)
\(\Leftrightarrow x=10\)
b.
\(\dfrac{3\left(2x+1\right)}{4}-5x+\dfrac{3}{6}+\dfrac{x+1}{3}=\dfrac{x+7}{2}\)
\(\Leftrightarrow\dfrac{3.3\left(2x+1\right)-5x.12+3.2+\left(x+1\right).4}{12}=\dfrac{\left(x+7\right).6}{12}\)
\(\Leftrightarrow18x+9-60x+6+4x+4=6x+42\)
\(\Leftrightarrow18x-60x+4x-6x=42-9-6-4\)
\(\Leftrightarrow-44x=23\)
\(\Leftrightarrow\dfrac{-23}{44}\)
Hình như mình làm bị sai sai
