1. Flashback
Write an equation for the line that satisfies the given conditions.
1) through: (1, 2), slope = 7
2) through: (4, 2), parallel to y =-3/4 x- 5
3) through: (2, 5), slope = undefined

2. Joke of the day
There are three types of people in the world, those who can count and those who can't.

4. Regression Analysis
The process of finding a curve that most closely fits a set of data.
The curve is called the regression curve.
A line is considered a curve in this situation.

5. Steps for Regression analysis
Plot the data on a scatter plot.
Find the regression equation. (Line of best fit in this situation.)
Graph the regression equation on the scatter plot to see the fit.
Use the regression equation to predict values not given by data.

6. Example Year Population (millions) 1980 4454 1985 4853 1990 5285 1995
5696
2003
6305
2004
6378
2005
6450

7. Steps Enter data into calculator. (STAT, edit, L1, L2)
Turn stat plot on. (2nd, y=, on, enter)
Change window (window, x and y values will need to be changed)
Calculate linear regression. (STAT, CALC, 4)
Enter equation into calculator (y=)
Graph. Compare line to stat plot.

8. Graphically Algebraically Y= 79.957x-153848.716
We are looking for a prediction of population in 2010, so substitute for x.
or about 6865
Graphically
Find value at

9. Interpret
The population in 2010 should be about 6865 million people according to the regression.

10. Now, it’s your turn… Complete the worksheet with a partner.
Be prepared to present your solutions with the class.

11. Exit Slip
Use the table that shows the number of goals Pierre scored playing hockey to answer problems 1–3. 1. Using the data from 2001 and 1997, find the slope of the line. 2. With your answer from problem 1 and the point (2000, 19), write an equation for the line in slope-intercept form. 3. Using your answer from problem 2, how many goals should Pierre score in 2004?
Year
Goals
1997 26
1998 24
1999 20
2000 19
2001 15