Notes with answers - Summit Schools

Your Notes
Homework
Example 3 Use a Best-Fitting Line
Use the equation of the best-fitting line from Example 2
to predict the number of people that will attend the
tenth football game.
Solution
Substitute 10 for x in the equation from Example 2.
y 5 25( 10 ) 1 700 5 250 1 700 5 950
You can predict that 950 people will attend the game.
Checkpoint Complete the following exercises.
For each scatter plot, tell whether the data show a
positive correlation, negative correlation, or relatively no
correlation.
1. y
2. y
1
O
1
positive correlation
x
1
O
1
relatively no correlation
3. School The table gives the average class score y on
each test for the first six chapters x of the textbook.
x 1 2 3 4 5 6
y 84 83 86 88 87 90
a. Approximate the best-fitting
line for the data.
y 5 2x 1 80
b. Use your equation to predict
the test score for the 9th test
that the class will take.
98
Average class score
90
88
86
84
82
y
0
0 1 2 3 4 5
Test
Copyright © McDougal Littell/Houghton Mifflin Company Lesson 2.7 • Algebra 2 C&S Notetaking Guide 45
x
6
x