**Chapter 1Linear Equations and Inequalities**

1.1 Properties of Real Numbers

1.2 Equations

1.3 Absolute Value Equations

1.4 Inequalities

1.5 Compound Inequalities

1.6 Absolute Value Inequalities

**1.1 Properties of Real Numbers**

*Real numbers* are the set of numbers made up of all rational and irrational numbers. Subsets of rational numbers include integers, whole numbers, and natural numbers.

• *Natural Numbers*: Often called “counting numbers” {1, 2, 3, 4, ...}.

• *Whole Numbers*: Natural numbers and 0 {0, 1, 2, 3, 4, ...}.

• *Integers*: Whole numbers and their negatives {..., –3, –2, –1, 0, 1, 2, 3, ...}.

• *Rational Numbers*: Numbers that can be written as a ratio of two integers and the denominator of the ratio is not 0, such as.

• *Irrational Numbers*