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.

$$ \begin{array}{c|rrr}\color{blue}{3}&-25&18&-20\\& & & \\ \hline &&& \end{array} $$

Step 1 : Bring down the leading coefficient to the bottom row.

$$ \begin{array}{c|rrr}3&\color{orangered}{ -25 }&18&-20\\& & & \\ \hline &\color{orangered}{-25}&& \end{array} $$

Step 2 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 3 } \cdot \color{blue}{ \left( -25 \right) } = \color{blue}{ -75 } $.

$$ \begin{array}{c|rrr}\color{blue}{3}&-25&18&-20\\& & \color{blue}{-75} & \\ \hline &\color{blue}{-25}&& \end{array} $$

Step 3 : Add down last column: $ \color{orangered}{ 18 } + \color{orangered}{ \left( -75 \right) } = \color{orangered}{ -57 } $

$$ \begin{array}{c|rrr}3&-25&\color{orangered}{ 18 }&-20\\& & \color{orangered}{-75} & \\ \hline &-25&\color{orangered}{-57}& \end{array} $$

Step 4 : Multiply by the number on the left, and carry the result into the next column: $ \color{blue}{ 3 } \cdot \color{blue}{ \left( -57 \right) } = \color{blue}{ -171 } $.

$$ \begin{array}{c|rrr}\color{blue}{3}&-25&18&-20\\& & -75& \color{blue}{-171} \\ \hline &-25&\color{blue}{-57}& \end{array} $$

Step 5 : Add down last column: $ \color{orangered}{ -20 } + \color{orangered}{ \left( -171 \right) } = \color{orangered}{ -191 } $

$$ \begin{array}{c|rrr}3&-25&18&\color{orangered}{ -20 }\\& & -75& \color{orangered}{-171} \\ \hline &\color{blue}{-25}&\color{blue}{-57}&\color{orangered}{-191} \end{array} $$

Bottom line represents the quotient $ \color{blue}{ -25x-57 } $ with a remainder of $ \color{red}{ -191 } $.

Synthetic Division Calculator