In recent years, college students, like U.S. consumers as a whole, have increased
their dependency on credit cards. In 2008, 84% of undergraduates had at least one
credit card, up from 76% in 2004. The average (mean) outstanding balance for
undergraduates grew from $946 in 2004 to a record-high $3173 in 2008, with 92%
of these students using credit cards to pay direct education expenses. (Source:
Sallie Mae.)
In Example 7of Section 3.2,we examine a linear equation in two variables
that models credit card debt in the United States.
Linear Equations and
Inequalities in Two
Variables; Functions
3.1 Linear Equations
in Two Variables;
The Rectangular
Coordinate System
3.2 Graphing Linear Equations in Two Variables
3.3 The Slope of a Line
3.4 Writing and
Graphing Equations
of Lines
Summary Exercises on
Linear Equations and
Graphs
3.5 Graphing Linear
Inequalities in Two
Variables
3.6 Introduction to Functions
Functions
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CHAPTER