Beginning Algebra, 11th Edition

284 CHAPTER 4 Systems of Linear Equations and Inequalities

If the inequalities of a system are not solved for yas in this example, we must do

so in order to enter them into the calculator. Notice that we cannot determine from

the screen in FIGURE 17(b)whether the boundary lines are included or excluded in the

solution set. For this system, neither boundary line is included.

For Discussion or Writing

Use a graphing calculator to graph the solution sets of the systems of linear inequal-

ities from Examples 1 and 2.Compare your calculator graphs to the graphs in

FIGURES 14 AND 15on pages 282 and 283.

10

–10

–10 10

(a) (b)

FIGURE 17

Complete solution available
on the Video Resources on DVD

4.5 EXERCISES

Concept Check Match each system of inequalities with the correct graph from choices A– D.

1. A. B.

2.

3. C. D.

4.

Graph the solution set of each system of linear inequalities. See Examples 1 and 2.

y7- 3

x 65

y6- 3

x 75

yÚ- 3

x... 5

y...- 3

xÚ 5

x

y

(^05)
–3
x
y
(^05)
–3
x
y
(^05)
–3
x
y
(^05)
–3

5. 6. 7.

x- 2 y... 5

4 x+ 5 yÚ 20

x-yÚ 3

x+y... 2

x-yÚ 1

x+y... 6

8. 9. 10.

x- y6- 1

x+ 2 y 64

x- y 65

2 x+ 3 y 66

2 x- yÚ 4

x+ 4 y... 8

The crosshatched region

is the intersection of the

solution sets of the two

individual inequalities

and represents the solu-

tion set of the system.

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