Game Development Reference
In-Depth Information
3
4
¼
5
6
i. a
j.
8x
2
þ 3 x ¼ 24
Least Common Denominators and Clearing Fractions
In the previous section, you multiplied by given values (such as 7) to get rid
fractions. This activity is known generally as clearing an equation of fractions. To
clear a fraction in an efficient way, you often make use of least common
denominators. The least common denominator (LCD) is the number you get if
you multiply together the denominators of the terms of the equation.
The least common denominator allows you to evaluate the terms of an equation
according to a common denominator value. From there, you can then proceed to
cancel terms. Here is an equation worked with on this basis:
x
3
þ
4
7
¼
2
3
¼
21
x
3
þ
4
7
2
3
21
2
3
21
x
3
þ
21
ð
4
7
¼
21
1
LCD is 21
:
Clearing the fraction.
7
x þ
12
¼
14
7
x þ
12
12
¼
14
12
Undoing the addition
:
7
x ¼
2
7
x
7
¼
2
7
Undoing the multiplication
:
2
7
x ¼
With this equation, you multiply by 21, which you arrive at using the common
multiples of 3 and 7. This is the least common denominator. After multiplying
the terms of the equation by 21, you cancel terms and reduce the fractions. By
