Activities

1. Draw a line of best fit on the graph below.

2. What is the equation of the line of best fit on the graph below?

3. Write the equation for the line of best fit that could be used to represent the data below.

4. Does the line of best fit for the following coordinate points have a positive or negative slope?

5. Estimate, to the nearest tenth, the y-intercept of the line of best fit for the data shown below.

6. Plot the points from the data below on the graph, and then draw a line of best fit to match the data.

7. Draw a line of best fit on the graph below. Now fill in the blanks (estimate to the nearest tenth) on the table using the line of best fit.

8. Below is a graph of the money remaining in a college student’s bank account at the end of each month. Determine an equation for the line of best fit for the data.

9. Sasha has been measuring the height in inches of one of her garden plants each day. She plotted her results on the graph below. Use a line of best fit to estimate the height of Sasha’s plant after 15 days.

10. A student carried out a science experiment where she recorded the length of a metal spring when various masses were hung from it. Her data is shown below.

Use a scatterplot and line of best fit to estimate the length of the spring when (a) no mass is hung from it and (b) a mass of 250 g is hung from it.

11. The table below shows the number of hurricanes per year that reached landfall in the United States. Plot the data on the graph below and then draw a line of best fit for the data.

12. A person’s shoe size is dependent on their height. A table below gives examples of the height of various male students and their shoe size. Create a scatter plot to determine the equation of the line of best fit for the data.

13. A line of best fit is created for the following data. The equation of the line is y = -0.75x + 12. Which of the data points is furthest from the line?

14. Is it possible to have a line of best fit using the following four points (3, 3), (-3, 3), (-3, -3), (3, -3)?

15. Draw a line of best fit on the graph shown below.

16. Explain, in your own words, how you can tell if a line of best fit for a scatterplot will be a good or bad way to explain the data?

17. Rank the following relations in order from which one would have the line of best fit closest to all the data to the one whose line of best fit would not fit the data at all.

1. A person's height based on their age
2. A person's money saved based on their age
3. A person's IQ based on their age
4. A person's number of children they have based on their age
5. A person's yearly income based on their age
6. A person's age based on their age

18. Create 7 coordinate points that would result in a line of best fit of y = -2x + 3 but are not exactly on the line.

19. What is a possible slope of the line of best fit for the data shown here? 

20. What could be the equation of the line of best fit for the data shown below?

21. Below is a scatter plot depicting the number of words children understand, based on their age, in years. Estimate the slope for the line of best fit for this data.

22. Without using a graph, determine the equation of the line of best fit of the following four points:  (1, 4), (3, 4), (4, 7), (6, 7).

23. What could be the equation of the line of best fit of the following scatterplot?

24. Trisha is determining a line of best fit for height based on age of the students in her high school. How would the equation change if she did not include the basketball team?

25. Create a story about your friend Maverick who is researching the size of an animal in the amazon jungle. Create data for the weight of the animal being studied based on its age. Finally, determine the equation for the line of best fit for your specific species of animal.

Answer Key/Rubric

2. y = 3

3. y = -x + 10

4. Negative

5. Approximately b = 0.5

8. Various answers including: s = -4m + 360

9. Various answers including 11 inches

10. (a) 4.8 cm (b) 10.1 cm

11. Various answers including y = 2

12. S = 0.22h - 6

13. (10, 7)

14. It is not possible because there is zero correlation between the input and output

16. Various answers including: If the data looks like it generally forms a straight line, meaning all of the points are close to a line that goes between them, then the line of best fit is helpful. If the points are scattered in a random fashion then it is not helpful to use a line of best fit.

17. Various answers including:  f, d, e, b, a, c

18. Various answers including: (0, 4), (1, 0), (2, 0), (3, -4), (4, -6), (5, -5), (6, -10)

19. m = 2

20. y = -x + 10

21. 325 words per year

22. y = x + 2

23. Various answers, but they should have a slope of ½ or less and a positive y-intercept. For example

24. The slope would become smaller and the starting point would become larger

25. Various stories including Maverick was studying anaconda’s in order to determine the weight capacity of an enclosure he was planning on using to transfer an injured species to an animal rehab center in the US. Line of best fit: W = 33a + 5