The synthetic division table is:
$$ \begin{array}{c|rrr}6&3&-10&0\\& & 18& \color{black}{48} \\ \hline &\color{blue}{3}&\color{blue}{8}&\color{orangered}{48} \end{array} $$The solution is:
$$ \frac{ 3x^{2}-10x }{ x-6 } = \color{blue}{3x+8} ~+~ \frac{ \color{red}{ 48 } }{ x-6 } $$Step 1 : Write down the coefficients of the dividend into division table. Put the zero from $ x -6 = 0 $ ( $ x = \color{blue}{ 6 } $ ) at the left.
$$ \begin{array}{c|rrr}\color{blue}{6}&3&-10&0\\& & & \\ \hline &&& \end{array} $$Step 1 : Bring down the leading coefficient to the bottom row.
$$ \begin{array}{c|rrr}6&\color{orangered}{ 3 }&-10&0\\& & & \\ \hline &\color{orangered}{3}&& \end{array} $$Step 2 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 6 } \cdot \color{blue}{ 3 } = \color{blue}{ 18 } $.
$$ \begin{array}{c|rrr}\color{blue}{6}&3&-10&0\\& & \color{blue}{18} & \\ \hline &\color{blue}{3}&& \end{array} $$Step 3 : Add down last column: $ \color{orangered}{ -10 } + \color{orangered}{ 18 } = \color{orangered}{ 8 } $
$$ \begin{array}{c|rrr}6&3&\color{orangered}{ -10 }&0\\& & \color{orangered}{18} & \\ \hline &3&\color{orangered}{8}& \end{array} $$Step 4 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 6 } \cdot \color{blue}{ 8 } = \color{blue}{ 48 } $.
$$ \begin{array}{c|rrr}\color{blue}{6}&3&-10&0\\& & 18& \color{blue}{48} \\ \hline &3&\color{blue}{8}& \end{array} $$Step 5 : Add down last column: $ \color{orangered}{ 0 } + \color{orangered}{ 48 } = \color{orangered}{ 48 } $
$$ \begin{array}{c|rrr}6&3&-10&\color{orangered}{ 0 }\\& & 18& \color{orangered}{48} \\ \hline &\color{blue}{3}&\color{blue}{8}&\color{orangered}{48} \end{array} $$Bottom line represents the quotient $ \color{blue}{ 3x+8 } $ with a remainder of $ \color{red}{ 48 } $.