Question
Multiply polynomial $ \, \color{blue}{ 2x+1 } \, $ by $ \, \color{orangered}{ x+4 }$.
Answer
$$ \left( \color{blue}{2x+1} \right) \cdot \left( \color{orangered}{x+4} \right) = 2x^2+9x+4 $$
Explanation
In this example we are multiplying two binomials so FOIL method can be used.
$$ \begin{aligned} \left( \color{blue}{ 2x+1}\right) \cdot \left( \color{orangered}{ x+4}\right) &= \underbrace{ \color{blue}{2x} \cdot \color{orangered}{x} }_{\text{FIRST}} + \underbrace{ \color{blue}{2x} \cdot \color{orangered}{4} }_{\text{OUTER}} + \underbrace{ \color{blue}{1} \cdot \color{orangered}{x} }_{\text{INNER}} + \underbrace{ \color{blue}{1} \cdot \color{orangered}{4} }_{\text{LAST}} = \\ &= 2x^2 + 8x + x + 4 = \\ &= 2x^2 + 8x + x + 4 = \\ &= 2x^2+9x+4; \end{aligned} $$This page was created using
Polynomial Operations Calculator