The synthetic division table is:
$$ \begin{array}{c|rrrr}3&6&-19&1&6\\& & 18& -3& \color{black}{-6} \\ \hline &\color{blue}{6}&\color{blue}{-1}&\color{blue}{-2}&\color{orangered}{0} \end{array} $$The solution is:
$$ \frac{ 6x^{3}-19x^{2}+x+6 }{ x-3 } = \color{blue}{6x^{2}-x-2} $$Step 1 : Write down the coefficients of the dividend into division table. Put the zero from $ x -3 = 0 $ ( $ x = \color{blue}{ 3 } $ ) at the left.
$$ \begin{array}{c|rrrr}\color{blue}{3}&6&-19&1&6\\& & & & \\ \hline &&&& \end{array} $$Step 1 : Bring down the leading coefficient to the bottom row.
$$ \begin{array}{c|rrrr}3&\color{orangered}{ 6 }&-19&1&6\\& & & & \\ \hline &\color{orangered}{6}&&& \end{array} $$Step 2 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 3 } \cdot \color{blue}{ 6 } = \color{blue}{ 18 } $.
$$ \begin{array}{c|rrrr}\color{blue}{3}&6&-19&1&6\\& & \color{blue}{18} & & \\ \hline &\color{blue}{6}&&& \end{array} $$Step 3 : Add down last column: $ \color{orangered}{ -19 } + \color{orangered}{ 18 } = \color{orangered}{ -1 } $
$$ \begin{array}{c|rrrr}3&6&\color{orangered}{ -19 }&1&6\\& & \color{orangered}{18} & & \\ \hline &6&\color{orangered}{-1}&& \end{array} $$Step 4 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 3 } \cdot \color{blue}{ \left( -1 \right) } = \color{blue}{ -3 } $.
$$ \begin{array}{c|rrrr}\color{blue}{3}&6&-19&1&6\\& & 18& \color{blue}{-3} & \\ \hline &6&\color{blue}{-1}&& \end{array} $$Step 5 : Add down last column: $ \color{orangered}{ 1 } + \color{orangered}{ \left( -3 \right) } = \color{orangered}{ -2 } $
$$ \begin{array}{c|rrrr}3&6&-19&\color{orangered}{ 1 }&6\\& & 18& \color{orangered}{-3} & \\ \hline &6&-1&\color{orangered}{-2}& \end{array} $$Step 6 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 3 } \cdot \color{blue}{ \left( -2 \right) } = \color{blue}{ -6 } $.
$$ \begin{array}{c|rrrr}\color{blue}{3}&6&-19&1&6\\& & 18& -3& \color{blue}{-6} \\ \hline &6&-1&\color{blue}{-2}& \end{array} $$Step 7 : Add down last column: $ \color{orangered}{ 6 } + \color{orangered}{ \left( -6 \right) } = \color{orangered}{ 0 } $
$$ \begin{array}{c|rrrr}3&6&-19&1&\color{orangered}{ 6 }\\& & 18& -3& \color{orangered}{-6} \\ \hline &\color{blue}{6}&\color{blue}{-1}&\color{blue}{-2}&\color{orangered}{0} \end{array} $$Bottom line represents the quotient $ \color{blue}{ 6x^{2}-x-2 } $ with a remainder of $ \color{red}{ 0 } $.