Question
Subtract polynomials: $ \, \color{blue}{ x^2-8x-9 } \, $ , $ \, \color{orangered}{ 3x^2-6x-6 }$.
Answer
$$ \left( \color{blue}{x^2-8x-9} \right) - \left( \color{orangered}{3x^2-6x-6} \right) = -2x^2-2x-3 $$
Explanation
Step 1: Write second polynomial below the first one. Making sure like terms are lined up.
$$ \begin{array}{lrrr} & x^2 & -8x & -9 \\ \color{red}{ - } & 3x^2 & -6x & -6 \\ \hline \end{array} $$Step 2: Change ALL the signs in the second row.
$$ \begin{array}{lrrr} & x^2 & -8x & -9 \\ \color{red}{ - } & -3x^2 & 6x & 6 \\ \hline \end{array} $$Step 3: Combine like terms (add each column):
$$ \begin{array}{lrrr} & x^2 & -8x & -9 \\ \color{red}{ - } & -3x^2 & 6x & 6 \\ \hline & 4x^2 & -14x & -15 \end{array} $$This page was created using
Polynomial Operations Calculator