Game Development Reference
In-Depth Information
Multiplication and Division
When you work with multiplication and division to solve equations, your actions
proceed along lines similar to those you use when you work with addition and
subtraction. Because division often involves work with fractions, however, your
activities take on greater complexity. Still, the essential work of maintaining equality
between expressions remains the same. Here is an equation you solve using division:
2x
¼
10
To or undo the relationship between 2 and
x
, you divide the expression by 2.
When you divide by 2, you employ the multiplicative inverse of 2. The effect of
this activity is to transform the coefficient of
x
into 1 while dividing 10 in a way
that equates with this action. Here is how you proceed:
2
x
2
¼
10
2
1
2
Multiply by the multiplicative inverse of 2, or
1
x ¼
5
x ¼
5
The multiplication brings about a division of 10 by 2. At the same time, it isolates
x
.
When you undo a relation between two terms, you are able to isolate one of the
terms to discover its value. As Figure 5.3 illustrates, as long as the operations you
perform on both sides of the equation result in equal changes, you can proceed
with such activities until you reach the solution of the equation.
What applies to division also applies to multiplication. Here is an equation that
begins with a division:
x
3
¼
7
Figure 5.3
Equations allow you to do and undo operations.
