1. During the winter, a horse requires about 36 liters of water per day and a sheep requires about 3.6 liters per day. A farmer is able to supply his horses and sheep with a total of 300 liters of water each day. Write and inequality that represents the possible number of horses and sheep this farmer can keep.
Problem of the Day

2. Section 2-5 Scatter Plots and Lines of Regression

3. Then Now Objectives You wrote linear equations.
Use scatter plots and prediction equations.
Model data using lines of regression.

4. Common Core State Standards
Content Standards
Common Core State Standards
F.IF.4 – For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship.
Mathematical Practices
4) Model with mathematics. 5) Use appropriate tools strategically.

5. Bivariate Data: data with two variables
Bivariate Data: data with two variables. Scatter Plot: a set of bivariate data graphed as ordered pairs in a coordinate plane.
Vocabulary

6. Line of Fit
Scatter Plots

7. If x = 10, find y.
Example 1 x y 1 3 5 4 7 6 11 13 10

8. Regression Line: determined through complex calculations to ensure that the distance of all data points to the line of fit are at a minimum.
Vocabulary

9. Year
Sales (%)
1995
52.0
1996
49.9
1997
51.8
1998
50.8
1999
44.5
2000
42.4
2001
42.5
2002
36.8
2003
33.2
2004
32.5
The table shows the percent of sales that were made in music stores in the US for the period – Use your calculator to make a scatter plot of the data. Find and graph the line of regression. Then use the function to predict the percent of sales made in a music store in 2018.
Example 2

10. Year
Sales (%)
1995
52.0
1996
49.9
1997
51.8
1998
50.8
1999
44.5
2000
42.4
2001
42.5
2002
36.8
2003
33.2
2004
32.5

11. Year
Income ($)
1970
9867
1980
21,023
1985
27,735
1990
35,353
1995
40,611
1998
46,737
2000
50,732
2002
51,680
The table shows the median income of US family for the period Use your calculator to make a scatter plot of the data. Find an equation for and graph the line of regression. Then use the equation to predict the median income in 2020.
Example 2

12. Year
Income ($)
1970
9867
1980
21,023
1985
27,735
1990
35,353
1995
40,611
1998
46,737
2000
50,732
2002
51,680

13. p.96 #2, 7, 8, 23
Homework