Linear Function and Cake Production

A small bakery produces a certain type of cake, and the quantity produced each day can be modeled by a linear function. If the bakery produces 50 cakes on Monday and 70 cakes on Wednesday, determine the linear function that describes the number of cakes produced, where the input is the number of days since Monday (0 for Monday, 1 for Tuesday, and so on).

Let $C(x)$ represent the number of cakes produced on day $x$, where $x$ is the number of days since Monday. The output for Monday ($x = 0$) is 50 cakes, so $C(0) = 50$. For Wednesday ($x = 2$), the production is 70 cakes, so $C(2) = 70$. Find $C(4)$, which represents the number of cakes produced on Friday.