When the cost of the 3-D printer is $800, the equation in Example 5 can be rewritten as below.
c=50m+800/m
We will first graph the equation. To draw a graph on our calculator, we first have to press Y= and write the function on one of the rows. Having written the function, we can press GRAPH to draw it. While we are writing the function we will replace m and c with x and y, respectively.
To observe the graph properly, we can set the viewing window as shown below.
Next, we press TRACE. Then we will use the right and left arrow keys to move along the graph to get y≈ 90.
The average cost falls to $90 per model after about 20 models are printed. Now, we will examine the average cost as more models are printed. To do that we will use the table feature of our graphing calculator. We will first change the table settings as below by pushing 2ND and WINDOW.
Now, we can push 2ND and GRAPH to see the table.
Let's also examine the average cost for greater amounts.
The tables show that the average cost approaches $50 as more models are printed.
