Basic Mathematics for College Students

2.1 An Introduction to the Integers 135

The Language of Mathematics Netrefers to what remains after all the

deductions (losses) have been accounted for.Net incomeis a term used in

business that often is referred to as the bottom line. Net income indicates

what a company has earned (or lost) in a given period of time (usually

1 year).

“The most dangerous pitfall for many college students is the overuse of credit

cards. Many banks do their best to entice new card holders with low or zero-interest

cards.”

Gary Schatsky, certified financial planner

Which numbers on the credit card statement below are actually debts and,

therefore, could be represented using negative numbers?

THINK IT THROUGH Credit Card Debt

Previous

Balance

Billing Date Date Payment Due Minimum payment

New Purchases Payments &

Credits

New Balance

$4,621

Account Summary

$1,073 $2,369 $3,325

Periodic rates may vary.

See reverse for explanation and important information.

BANK STAR Please allow sufficient time for mail to reach Bank Star.

04/21/10 05/16/10 $67

3 Use inequality symbols to compare integers.

Recall that the symbol means “is less than” and that means “is greater than.” The
figure below shows the graph of the integers and 1. Since is to the left of 1 on
the number line, 2  1. Since  2  1 , it is also true that 1  2.

 2  2

 

− 4 − 3 − 2 −101 23 4

EXAMPLE (^2) Place an or an symbol in the box to make a true
statement. a. 4 b.
StrategyTo pick the correct inequality symbol to place between the pair of
numbers, we will determine the position of each number on the number line.
WHYFor any two numbers on a number line, the number to the leftis the smaller
number and the number on the rightis the larger number.
Solution
a.Since 4 is to the right of on the number line,.
b.Since  8 is to the left of  7 on the number line, 8  7.

 5 4  5

 5  8  7

 

Self Check 2

Place an or an symbol in the

box to make a true statement.

a. 6

b.

Now TryProblems 31 and 35

 11  10

 6