1. A scatterplot can be used to show whether there is a relationship between two sets of data.

2. Example 5-1a Education The table below shows the approximate percent of students who sent applications to two colleges in various years since 1985. Make a scatter plot of the data. Graph the data as ordered pairs, with the number of years since 1985 on the horizontal axis and the percentage on the vertical axis. 13 14 15 15 18 20 Percent 15 12 9 6 3 0 Years Since 1985 Source: U.S. News & World Report

3. Example 5-2a Draw a line of best fit for the data. How well does the line fit the data? The points (3 , 18) and (15 , 13) appear to represent the data well. Draw a line through these two points. 13 14 15 15 18 20 Percent 15 12 9 6 3 0 Years Since 1985 Source: U.S. News & World Report

4. Example 5-2a What is the equation of the line of best fit? The points (3 , 18) and (15 , 13) appear to represent the data well. Draw a line through these two points. m = 18 – 13 = -5 3 – 15 12 y – y 1 = m(x – x 1 ) y – 18 = -5 (x – 3) 12 y – 18 = -5 x + 5 12 4 y = -5 x + 79 12 4 13 14 15 15 18 20 Percent 15 12 9 6 3 0 Years Since 1985 Source: U.S. News & World Report