Question: The cost of planting seed is usually a function of the number of acres sown. The cost of the equipment is a fixed cost because it must be paid regardless of the number of acres planted. The costs of supplies and labor vary with the number of acres planted and are called variable costs. Suppose the fixed costs are $10,000 and the variable costs are $200 per acre. Let C be the total cost, measured in thousands of dollars, and let x be the number of acres planted.
(a) Find a formula for C as a function of x.
(b) Graph C against x.
(c) Which feature of the graph represents the fixed costs? Which represents the variable costs?