Lesson 4.3 Scatter Plot

Scatter Plots and Best Fit Line

​Mrs. Richmond



- What information can you gather from the scatter plot shown in the image?

-What is the relationship shown here?

-As the daily temperature goes increases what happens to visitors?

What is a scatter plot?

A scatter plot shows the relationship between a set of data with two variables, graphed as ordered pairs on a coordinate plane. The relationship is known as a correlation or association.

​1. How can you determine which is positive and negative?

2.How can you determine if a scatter plot has no correlation?

Multiple Choice

Determine the correlation.

• positive

• negative

• no correlation

Multiple Choice

• positive

• negative

• no correlation

Multiple Choice

Determine the correlation.

• positive

• negative

• no correlation

Best Fit Line

?As time increases baseball average prices _______.

Multiple Choice

What information does the trend line give relating to the relationship between time (years) average prices?

• as time increases average baseball tickets increases

• as time increases average baseball tickets decrease

Multiple Choice

Determine the correlation.

• positive

• negative

• no correlation

• 8

Best Fit Line (Linear regression)

• Graph the given data.

• Draw a line that represents the trend of the data.

• Find the slope of two points on the line.

• Find the y-intercept.

• Write the equation.

• Graph the given data.

Write the equation of the line.

​

How to use the TI-84 to find the line that best fits.

Use your calculator tip sheet to jot down how to find the line that best fits using your calculator.
Watch the YouTube Video, jot down some steps, take notes, and practice.

Multiple Choice

Use (1997, 13) and (2005, 22) to find the slope.

• 8/9

• 9/8

• 9

• 8

Multiple Choice

Find the line of best fit

• y = 0.20x + 26

• y = 26x + 0.20

• y = 25x + 28

• y = 28x + 25

Multiple Choice

Find the line of best fit

• y = 1.2x + 22

• y = 22x + 1.2

• y = 12x + 47

• y = 47x + 12

Multiple Choice

Find the line of best fit

• y = -5.4x + 10840

• y = 10840x - 5.4

• y = 2001x + 39

• y = 39x + 2001

Multiple Choice

The equation of the trend line is y= 1/2x +1
How many laps can a bicycle make around the park in 23 minutes?

• 44 laps
• 12 1/2 laps
• 23 laps

Multiple Choice

Given the table, write the equation in the slope-intercept form.

• y = 1/3x + 6
• y = 3x + 6
• y = 2x + 6
• y = 1/2x + 6

Multiple Choice

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books.  Use the trend line to predict how many chapters would be in a book with 180 pages. 

• 12 chapters
• 15 chapters
• 18 chapters
• 21 chapters