EXAMPLE
Checking Solutions
2Tell whether the given value is a solution of the inequality.a. x+1 > 7; xx+1 > 7 Write the inequality.
=
8
x
.
b. 7y< 27; y7y<27 Write the inequality.
=
4
y
.
c. z3≥ 5; z=z—3≥ 5 Write the inequality.?
—
15
.
÷
x
≤
10
Exercises 11–16
Value of
x
x
+
3
≤
7
Is the inequality true?
3
3
+
3
≤
?
7
6
≤
7
✓
yes
4
4
+
3
≤
?
7
7
≤
7
✓
yes
5
5
+
3
≤
?
7
8
≤
/
7
✗
no

Ź
1
Ź
3
Ź
4
Ź
2
0
1
5
4
2
Ź
5
3
Use an open circle because
2 is
not
a solution.
Test a number to the left of 2.
g
â
0 is
not
a solution.
Test a number to the right of 2.
g
â
3 is a solution.
328
Chapter 7
Equations and Inequalities
EXAMPLE
Graphing an Inequality
3
Graph
g
> 2.
Ź
1
Ź
3
Ź
4
Ź
2
0
1
5
4
2
Ź
5
3
Shade the number line on the side where you
found the solution. The graph shows there are
infinitely many
solutions.
EXAMPLE
Real-Life Application
4The NASA Solar Probe Plus can withstand temperatures up to and including 2600°F. Write and graph an inequality that represents the temperatures the probe can withstand.
p
≥
−
3
Reading
The inequality
g
>
2 is
the same as 2
<
g
.