Chapter 5. Functions and More Functions

In Chapter 4 you examined fundamental notions related to presenting numerical data in graphical form. The discussion ended with a review of approaches to representing and working with functions. In this chapter, you take up the theme of working with equations, which allows you to solve the problems that functions embody. When you solve an equation, you work with addition and multiplication to “undo” operations so that you can solve the equation for a specific value. You also make use of least common denominators to clear equations of fractions. When you solve equations, you can end up with a single solution or a set of solutions. Among the equations that generate sets of solutions are those involving absolute values and inequalities. A review of these concepts at this point helps focus the activities of previous chapters so that you can begin using Cartesian graphical representations to work with linear equations. Among topics this chapter covers are the following:

• Rethinking the fundamentals of equations

• Uses of addition and subtraction

• Dealing with fractions

• Absolute values and the number line

• Inequalities and the number line