Section 3-5 - Rational Numbers and Equations
• multiply reciprocals
• solving equations involving rational numbers
1
Rational Numbers
What are rational numbers?
a real number that can be written as a fraction or a ratio of
two integers
What are some examples of rational numbers?
2
Solve the equations.
Example 1:
2 y=2
5
3
Reciprocals
What are reciprocals?
4
Reciprocals
What is the reciprocal of ......
4
5
,
1
6
,6
5
4
7
8
,
_ 14
51
8
7
,
_ 51
14
_2
3
,
_3
2
8,
1
8
5
Reciprocals
Example 2:
2
y=2
5
6
Reciprocals
Example 3:
_3
x=8
4
Example 4:
_ 4c
= -2
9
Example 5:
_1
(3x - 5) = 7
2
7
Multiplying by a Common Denominator
Example 6: Your test scores are 92 and 89. What is
the lowest score you can get on your next test to get
an A for the nine weeks.
What percentage is an A?
What are we looking for?
92 + 82 + x = 93
3
8
Homework:
pg: 130 # 9 - 33 all
9