Find $ \left(x+6\right)^2 $ using formula.

$$ (A + B)^2 = \color{blue}{A^2} + 2 \cdot A \cdot B + \color{red}{B^2} $$

where $ A = \color{blue}{ x } $ and $ B = \color{red}{ 6 }$.

$$ \begin{aligned}\left(x+6\right)^2 = \color{blue}{x^2} +2 \cdot x \cdot 6 + \color{red}{6^2} = x^2+12x+36\end{aligned} $$

Multiply each term of $ \left( \color{blue}{x+13}\right) $ by each term in $ \left( x^2+12x+36\right) $.

$$ \left( \color{blue}{x+13}\right) \cdot \left( x^2+12x+36\right) = x^3+12x^2+36x+13x^2+156x+468 $$

Combine like terms:

$$ x^3+ \color{blue}{12x^2} + \color{red}{36x} + \color{blue}{13x^2} + \color{red}{156x} +468 = x^3+ \color{blue}{25x^2} + \color{red}{192x} +468 $$

Multiply each term of $ \left( \color{blue}{x^3+25x^2+192x+468}\right) $ by each term in $ \left( x-4\right) $.

$$ \left( \color{blue}{x^3+25x^2+192x+468}\right) \cdot \left( x-4\right) = x^4-4x^3+25x^3-100x^2+192x^2-768x+468x-1872 $$

Combine like terms:

$$ x^4 \color{blue}{-4x^3} + \color{blue}{25x^3} \color{red}{-100x^2} + \color{red}{192x^2} \color{green}{-768x} + \color{green}{468x} -1872 = \\ = x^4+ \color{blue}{21x^3} + \color{red}{92x^2} \color{green}{-300x} -1872 $$

Multiply each term of $ \left( \color{blue}{x^4+21x^3+92x^2-300x-1872}\right) $ by each term in $ \left( x-9\right) $.

$$ \left( \color{blue}{x^4+21x^3+92x^2-300x-1872}\right) \cdot \left( x-9\right) = \\ = x^5-9x^4+21x^4-189x^3+92x^3-828x^2-300x^2+2700x-1872x+16848 $$

Combine like terms:

$$ x^5 \color{blue}{-9x^4} + \color{blue}{21x^4} \color{red}{-189x^3} + \color{red}{92x^3} \color{green}{-828x^2} \color{green}{-300x^2} + \color{orange}{2700x} \color{orange}{-1872x} +16848 = \\ = x^5+ \color{blue}{12x^4} \color{red}{-97x^3} \color{green}{-1128x^2} + \color{orange}{828x} +16848 $$