Basic Mathematics for College Students

Negative numbers can be represented on a

number lineby extending the line to the left and

drawing an arrowhead.

As we move to the right on the number line, the

values of the numbers increase. As we move to the

left, the values of the numbers decrease.

Graph 1, 6, 0,  4 , and 3 on a number line.

192 Chapter 2 The Integers

STUDY SKILLS CHECKLIST

Do You Know the Basics?

The key to mastering the material in Chapter 2 is to know the basics. Put a checkmark in the box

if you can answer “yes” to the statement.

I understand order on the number line:

and

I know how to add two integers that have the same

sign.

• The sum of two positive numbers is positive.


• The sum of two negative numbers is negative.

I know how to add two integers that have different

signs.

• If the positive integer has the larger absolute
  value, the sum is positive.


• If the negative integer has the larger absolute
  value, the sum is negative.
  12 (20) 8

 7  11  4

 4 (5) 9

4  5  9

 4  3  15  20

I know how to use the subtraction rule:Subtraction

is the same as addition of the opposite.

and

I know that the rules for multiplying and dividing

two integers are the same:

• Like signs: positive result

and

• Unlike signs: negative result

and

I know the meaning of a symbol:

(6) 6  0  60  6



 15

3

2(3) 6  5

 15

 3

(2)(3) 6  5

 9  3  9 (3) 12

 2 (7) 2  7  5

The collection of positive whole numbers, the

negatives of the whole numbers, and 0 is called the

set of integers.

Positive numbersare greater than 0 and negative

numbersare less than 0.

The set of positive integers:

The set of negative integers: {... , 5, 4, 3, 2, 1}

{1, 2, 3, 4, 5,... }

DEFINITIONS AND CONCEPTS EXAMPLES

The set of integers: {... , 5, 4, 3, 2, 1, 0, 1, 2, 3, 4, 5,... }

CHAPTER 2 SUMMARY AND REVIEW

SECTION 2.1 An Introduction to the Integers

Negative numbers Zero Positive numbers

Numbers get larger

Numbers get smaller

− 6 − 5 − 4 − 3 − 2 − 1012345 6