Area Problems

Example Continued

*Step 4.* Answer the questions.

- What is the domain?
- Since the inputs are based on width, the domain is all real numbers greater than or equal to 0; .

- What is the range?
- Since the outputs are based on area, the range is all real numbers greater than or equal to 0; .

- For what values of l is the area zero?
- This question is asking for the output to be zero, in other words the
*x*-intercepts, which are (0, 0) and (0, 400).

- This question is asking for the output to be zero, in other words the

- For what value of l is there a maximum area?
- This question is asking for the maximum value, in other words the vertex, which is (200, 80,000). The value of l that results in the maximum area is 200 feet.