The cost C(n), in dollars, of making n large cheese pizzas in a night shift is given by a linear equation. There is a fixed cost of $43.50. In addition there are wage costs of $4.50 per pizza. Write the equation to solve.

you know there is a fixed cost. So, start out with

C(n) = 43.50

Now, that does not depend on n. What does? The number of pizzas. Each costs 4.50, so the total cost of the wages is 4.50n

C(n) = 43.50 + 4.50n

Easy as (pizza) pie, right?