Multiply polynomial $ \, \color{blue}{ 2x+4 } \, $ by $ \, \color{orangered}{ x+9 }$.

$$ \left( \color{blue}{2x+4} \right) \cdot \left( \color{orangered}{x+9} \right) = 2x^2+22x+36 $$

In this example we are multiplying two binomials so FOIL method can be used.

$$ \begin{aligned} \left( \color{blue}{ 2x+4}\right) \cdot \left( \color{orangered}{ x+9}\right) &= \underbrace{ \color{blue}{2x} \cdot \color{orangered}{x} }_{\text{FIRST}} + \underbrace{ \color{blue}{2x} \cdot \color{orangered}{9} }_{\text{OUTER}} + \underbrace{ \color{blue}{4} \cdot \color{orangered}{x} }_{\text{INNER}} + \underbrace{ \color{blue}{4} \cdot \color{orangered}{9} }_{\text{LAST}} = \\ &= 2x^2 + 18x + 4x + 36 = \\ &= 2x^2 + 18x + 4x + 36 = \\ &= 2x^2+22x+36; \end{aligned} $$

Polynomial Operations Calculator