we have the linear equation
![p=(-(1)/(5))x+200](https://img.qammunity.org/2023/formulas/mathematics/college/exuz5kssg8ql21885z4r9s66ne1qvjd6h9.png)
Part A
the Revenue is equal to
R(x)=p*x
substitute
![R(x)=\lbrack(-(1)/(5))x+200\rbrack\cdot x](https://img.qammunity.org/2023/formulas/mathematics/college/xvblfphv14e8ojoyd657cyhsir5kuonpok.png)
![R(x)=-(1)/(5)x^2+200x](https://img.qammunity.org/2023/formulas/mathematics/college/b5qwj5gtnk8obg91umdobvy37wm68smugo.png)
Part B
the function of revenue is a quadratic equation (vertical parabola opens downward)
the vertex represents a maximum
using a graphing tool
see the attached figure
the vertex is the point (500, 50000)
therefore
the value of x that maximizes the revenue is
x=500
Part C
For x=500
Find out the unit price
![\begin{gathered} p=(-(1)/(5))(500)+200 \\ p=100 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/3apa9pu9bwr6er3amadzg297xmvx6b9mhf.png)
the unit price is p=$100
Part D
the maximum revenue is the y-coordinate of the vertex
the vertex is (500, 50,000)
therefore
the maximum revenue is $50,000