Question
Multiply polynomial $ \, \color{blue}{ 3x+6 } \, $ by $ \, \color{orangered}{ -3x+6 }$.
Answer
$$ \left( \color{blue}{3x+6} \right) \cdot \left( \color{orangered}{-3x+6} \right) = -9x^2+36 $$
Explanation
In this example we are multiplying two binomials so FOIL method can be used.
$$ \begin{aligned} \left( \color{blue}{ 3x+6}\right) \cdot \left( \color{orangered}{ -3x+6}\right) &= \underbrace{ \color{blue}{3x} \cdot \left( \color{orangered}{-3x} \right) }_{\text{FIRST}} + \underbrace{ \color{blue}{3x} \cdot \color{orangered}{6} }_{\text{OUTER}} + \underbrace{ \color{blue}{6} \cdot \left( \color{orangered}{-3x} \right) }_{\text{INNER}} + \underbrace{ \color{blue}{6} \cdot \color{orangered}{6} }_{\text{LAST}} = \\ &= -9x^2 + 18x + \left( -18x\right) + 36 = \\ &= -9x^2 + 18x + \left( -18x\right) + 36 = \\ &= -9x^2+36; \end{aligned} $$This page was created using
Polynomial Operations Calculator