Question
Subtract polynomials: $ \, \color{blue}{ 3x^2-7x+12 } \, $ , $ \, \color{orangered}{ x^2-8x+18 }$.
Answer
$$ \left( \color{blue}{3x^2-7x+12} \right) - \left( \color{orangered}{x^2-8x+18} \right) = 2x^2+x-6 $$
Explanation
Step 1: Write second polynomial below the first one. Making sure like terms are lined up.
$$ \begin{array}{lrrr} & 3x^2 & -7x & 12 \\ \color{red}{ - } & x^2 & -8x & 18 \\ \hline \end{array} $$Step 2: Change ALL the signs in the second row.
$$ \begin{array}{lrrr} & 3x^2 & -7x & 12 \\ \color{red}{ - } & -x^2 & 8x & -18 \\ \hline \end{array} $$Step 3: Combine like terms (add each column):
$$ \begin{array}{lrrr} & 3x^2 & -7x & 12 \\ \color{red}{ - } & -x^2 & 8x & -18 \\ \hline & 4x^2 & -15x & 30 \end{array} $$This page was created using
Polynomial Operations Calculator