Answer :
a.) To find the value of x to minimize C, we must differentiate the equation with respect with x and equate to 0.
dC(x) = 2x - 40 = 0
x = 20 hotdogs
b.) Substitute x = 20, to find the minimum cost
C = (20)^2 - 40(20) + 610
C = $ 210
dC(x) = 2x - 40 = 0
x = 20 hotdogs
b.) Substitute x = 20, to find the minimum cost
C = (20)^2 - 40(20) + 610
C = $ 210