Question
Multiply polynomial $ \, \color{blue}{ 4r-6 } \, $ by $ \, \color{orangered}{ 4r+6 }$.
Answer
$$ \left( \color{blue}{4r-6} \right) \cdot \left( \color{orangered}{4r+6} \right) = 16r^2-36 $$
Explanation
In this example we are multiplying two binomials so FOIL method can be used.
$$ \begin{aligned} \left( \color{blue}{ 4r-6}\right) \cdot \left( \color{orangered}{ 4r+6}\right) &= \underbrace{ \color{blue}{4r} \cdot \color{orangered}{4r} }_{\text{FIRST}} + \underbrace{ \color{blue}{4r} \cdot \color{orangered}{6} }_{\text{OUTER}} + \underbrace{ \left( \color{blue}{-6} \right) \cdot \color{orangered}{4r} }_{\text{INNER}} + \underbrace{ \left( \color{blue}{-6} \right) \cdot \color{orangered}{6} }_{\text{LAST}} = \\ &= 16r^2 + 24r + \left( -24r\right) + \left( -36\right) = \\ &= 16r^2 + 24r + \left( -24r\right) + \left( -36\right) = \\ &= 16r^2-36; \end{aligned} $$This page was created using
Polynomial Operations Calculator