ANSWER
![(L \bullet \: W)(x)= 10 {x}^(3) - 20 {x}^(2) + 65x](https://img.qammunity.org/2020/formulas/mathematics/high-school/f4zxwdffocff2mu2edgwun6cbrao37lnu0.png)
Step-by-step explanation
The length of a rectangle is represented by the function:
![L(x) = 5x](https://img.qammunity.org/2020/formulas/mathematics/high-school/qgcxjnmp8ql4qv5tsdnqjowgy95jw5pfhr.png)
and the width is represented by
![W(x)= 2 {x}^(2) - 4x + 13](https://img.qammunity.org/2020/formulas/mathematics/high-school/u35rewhqcuftsd42oqe4z34ktya928ay1s.png)
The area of a rectangle is calculated using the formula:
![Area = LW](https://img.qammunity.org/2020/formulas/mathematics/high-school/wsugorqpkic0ecq2po5ir1leeiayk8dflf.png)
In terms x, we have
![Area = (L \bullet \: W)(x)= L(x) * W(x)](https://img.qammunity.org/2020/formulas/mathematics/high-school/l2umt0at3cxmqhcckokfkrao4kunmrs08d.png)
We plug in the functions representing the length and width to obtain;
![(L \bullet \: W)(x)= 5x(2 {x}^(2) - 4x + 13)](https://img.qammunity.org/2020/formulas/mathematics/high-school/tp045xm63bl06phqz7ephtjmwiix4kvg3v.png)
We expand the parenthesis to obtain;
![(L \bullet \: W)(x)= 10 {x}^(3) - 20 {x}^(2) + 65x](https://img.qammunity.org/2020/formulas/mathematics/high-school/f4zxwdffocff2mu2edgwun6cbrao37lnu0.png)