Answer :
Let:
C = Total cost
R = Total revenue
x = Number of cakes
a = Cost of the ingredients for each cake = $1
b = Cost of a booth at the fair = $17
c = Selling price of each cake = $18
Therefore:
[tex]\begin{gathered} C=ax+b \\ C=x+17 \\ ------- \\ R=18x \end{gathered}[/tex]At some point, the club members will sell enough cakes so that their sales cover their expenditures. Therefore:
[tex]\begin{gathered} C=R \\ x+17=18x \\ _{\text{ }}solve_{\text{ }}for_{\text{ }}x\colon \\ 18x-x=17 \\ 17x=17 \\ x=\frac{17}{17} \\ x=1 \end{gathered}[/tex]Answer:
1 cake and $18