Answer:
<h3>Part A</h3>
The x-intercepts are reflecting zero-profit: (0, 0) and (6, 0).
The maximum value of the graph is at vertex (3, 120): maximum profit when the price is $3.
The function is increasing until the vertex, between x-value of 0 to 3 and is decreasing once it reached the vertex, between x-value of 3 to 6.
In the first interval the sale and profit increases, in the second interval the sale and profit decreases.
<h3>Part B</h3>
<u>Average rate of change from x = 3 to x = 5 is:</u>
- (f(5) - f(3))/(5 - 3) =
- (60 - 120)/2 = -30
This represents the profit drop of $30 per $1 price increase when price changes from $3 to $5.
<h3>Part C</h3>
- The domain is representing the price. It should be profitable so it is between $0 and $6.
