Game Development Reference
In-Depth Information
As an example of the effect of multiplying by a negative number, consider this
inequality:
6
5
4
x
ð
5
Þ
6
5
ð
5
Þð
4
xÞ
Multiply by
ð
5
Þ
to clear the fraction
:
ð
1
Þð
6
Þð
1
Þð
20
xÞ
Multiply by
ð
1
Þ
and reverse inequality to clear
the negative
:
6
20
x
Simplify
:
6
20
x
Divide by a positive number
:
No change
:
3
10
x
Reduce
:
When you multiply by
1 to make the inequality easier to work with, you render
the values on both sides of the inequality positive. This change makes it necessary
to reverse the inequality sign.
As in the previous example, to verify the correctness of the solution set, you can
first graph it on a number line.
To check the inequality, you can substitute the primary solution into the original
inequality:
6
5
4
3
10
6
5
12
10
6
5
6
5
Exercise Set 5.6
2
7
4
6
a. x þ
b.
4x
1
5
<
4
20
2
þ
