Activity
For questions 1 – 4, you will be provided with descriptions of four functions and four graphs representing the situation described below.
A child gets on a swing in a playground, swings for 30 seconds, and then gets off the swing.
The independent variable in each function is time, measured in seconds.
Link to Learning
Log into student.desmos.com using the information provided by your teacher to complete the activity.
1. Examine Graph A below.
Which function description best matches the representation provided in the graph? Be prepared to explain how you made your match.
- Function : The height of the swing, in feet, as a function of time since the child gets on the swing
- Function : The amount of time left on the swing as a function of time since the child gets on the swing
- Function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing
- Function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing
Function : The amount of time left on the swing as a function of time since the child gets on the swing
2. Examine Graph B below.
Which function description best matches the representation provided in the graph? Be prepared to explain how you made your match.
- Function : The height of the swing, in feet, as a function of time since the child gets on the swing
- Function : The amount of time left on the swing as a function of time since the child gets on the swing
- Function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing
- Function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing
Function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing
3. Examine Graph C.
Which function description best matches the representation provided in the graph? Be prepared to explain how you made your match.
- Function : The height of the swing, in feet, as a function of time since the child gets on the swing
- Function : The amount of time left on the swing as a function of time since the child gets on the swing
- Function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing
- Function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing
Function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing
4. Examine Graph D.
Which function description best matches the representation provided in the graph? Be prepared to explain how you made your match.
- Function : The height of the swing, in feet, as a function of time since the child gets on the swing
- Function : The amount of time left on the swing as a function of time since the child gets on the swing
- Function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing
- Function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing
Function : The height of the swing, in feet, as a function of time since the child gets on the swing
For questions 5 – 8, continue to use the scenario from above and include the following information to determine the domain and range for each function.
- The child is given 30 seconds on the swing.
- While the child is on the swing, an adult pushes the swing a total of 5 times.
- The swing is 1.5 feet (18 inches) above ground.
- The chains that hold the seat and suspend it from the top beam are 7 feet long.
- The highest point that the child swings up to is 4 feet above the ground.
[Hint: It may be helpful to revisit the scenario, the matched graph, and the additional list of information to identify specific values for the domain and range.]
5. Describe the domain and range for function : The height of the swing, in feet, as a function of time since the child gets on the swing.
- The domain is time in seconds, so it includes all numbers from 0 to 30.
- The range represents the height of the swing in feet so it includes all numbers from 1.5 to 4.
6. Describe the domain and range for function : The amount of time left on the swing as a function of time since the child gets on the swing.
- The domain is time in seconds, so it includes all numbers from 0 to 30.
- The range represents the amount of time left the child has to swing, in seconds, so it includes all numbers from 0 to 30.
7. Describe the domain and range for function : The distance, in feet, of the swing from the top beam (from which the swing is suspended) as a function of time since the child gets on the swing.
- The domain is time in seconds, so it includes all numbers from 0 to 30.
- The range represents the distance of the swing from the top beam in feet so it includes only one value, 7.
8. Describe the domain and range for function : The total number of times an adult pushes the swing as a function of time since the child gets on the swing.
- The domain is time in seconds, so it includes all numbers from 0 to 30.
- The range represents the total number of times an adult pushes the swing so it includes only the whole numbers from 0 to 5.
Self Check
Additional Resources
Describing Domain and Range Graphs
In a previous lesson, you explored the height, , of a bungee jumper at seconds.
Assuming the jump ended at 35 seconds, what is the domain?
For domain, consider the -values, so look from left to right.
The leftmost -value is 0, and the rightmost -value is 35.
The domain includes all the values from at least 0 up to and including 35 meters.
What are the values in the range?
For the range, consider the -values, so look from bottom to top.
The lowest -value is 10, and the highest -value is about 75.
So, the range includes all of the values from at least 10 up to about 75.
Try it
Try It: Describing Domain and Range Graphs
Describe the values of the domain and range using the graph below.
Your answers may vary, but here are some examples:
Here is how to find the domain and range values of this function:
For the domain, consider the -values on the graph.
The domain includes all of the values from at least 0 through and including 3.2.
For the range, consider the -values on the graph.
The range includes all of the values from at least 0 through and including 25.