Answer:
[tex]580x-10x^{2}[/tex]
[tex]580-20x[/tex]
Step-by-step explanation:
We have [tex]p=580-10x[/tex] where [tex]x[/tex] is the number of cakes sold per day and [tex]p[/tex] is the price.
Also, we have [tex]c=(30+5x)2[/tex] where [tex]x[/tex] is also the number of cakes and [tex]c[/tex] is the total cost.
The revenue would be
[tex](580-10x)x=580x-10x^{2}[/tex]
The marginal revenue would be the derivative of the revenue function
[tex]\frac{d}{dx}[580x-10x^{2} ] =580-20x[/tex]
Therefore, the answers are [tex]580x-10x^{2}[/tex] and [tex]580-20x[/tex], respectively.