<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />

# 5.4: What's My Rule

Difficulty Level: At Grade Created by: CK-12

Look at the table below. p\begin{align*}p\end{align*} and t\begin{align*}t\end{align*} stand for numbers. Can you write a rule to represent the relationship between p\begin{align*}p\end{align*} and t\begin{align*}t\end{align*}? Can you complete the table? In this concept we will learn how to write rules to represent what we see in tables.

### Guidance

In order to write rules for function tables like the one above, we can use the problem solving steps to help.

• First, describe what you see in the table.
• Second, identify what your job is. In these problems, your job will be to write the rule for the table.
• Third, make a plan. In these problems, your plan should be to look for a pattern to help you figure out the rule.
• Fourth, solve. In these problems, you will state the rule in an equation or in words and then complete the table.
• Fifth, check. In these problems you will check by making sure that the numbers in the table work with the rule.

#### Example A

Write the rule represented by the table. Then, complete the table.

Solution:

We can use problem solving steps to help.

\begin{align*}u\end{align*} \begin{align*}v\end{align*}
7 9
4 6
1 3
0 2
1. 2 4
2. 9 11
3. 3 5
4. 8 10
5. Rule: \begin{align*}v=u+2\end{align*}

#### Example B

Write the rule represented by the table. Then, complete the table.

Solution:

We can use problem solving steps to help.

\begin{align*}w\end{align*} \begin{align*}y\end{align*}
10 6
15 11
13 9
5 1
1. 8 4
2. 14 10
3. 7 3
4. 16 12
5. Rule: \begin{align*}y=w-4\end{align*}

#### Example C

Write the rule represented by the table. Then, complete the table.

Solution:

We can use problem solving steps to help.

\begin{align*}z\end{align*} \begin{align*}a\end{align*}
7 37
10 40
18 48
45 75
1. 31 61
2. 14 44
3. 8 38
4. 29 59
5. Rule: \begin{align*}a=z+30\end{align*}

#### Concept Problem Revisited

We can use problem solving steps to help.

### Vocabulary

A function is an example of a rule that states a relationship between two quantities. A variable is a letter that represents a number that can change value. In this concept, we wrote rules that stated how the two variables in the table were related.

### Guided Practice

Write the rule represented by each table. Then, complete each table.

1.

2.

3.

4.

Answers:

1. Here is the completed table and rule:

\begin{align*}b\end{align*} \begin{align*}c\end{align*}
48 28
50 30
28 8
42 22
1. 67 47
2. 59 39
3. 75 55
4. 34 14
5. Rule: \begin{align*}c=b-20\end{align*}

2. Here is the completed table and rule:

\begin{align*}d\end{align*} \begin{align*}e\end{align*}
3 12
8 32
2 8
5 20
1. 1 4
2. 7 28
3. 6 24
4. 9 54
5. Rule: \begin{align*}e=4 \times d\end{align*}

3. Here is the completed table and rule:

\begin{align*}f\end{align*} \begin{align*}g\end{align*}
10 2
40 8
25 5
5 1
1. 15 3
2. 35 7
3. 20 4
4. 45 9
5. Rule: \begin{align*}g=f \div 5\end{align*}

4. Here is the completed table and rule:

\begin{align*}h\end{align*} \begin{align*}j\end{align*}
2 18
5 45
7 63
1 9
1. 4 36
2. 3 27
3. 6 54
4. 9 81
5. Rule: \begin{align*}j=9 \times h\end{align*}

### Explore More

Write the rule represented by each table. Then, complete each table.

At Grade

Jan 18, 2013

## Last Modified:

Dec 29, 2014
Save or share your relevant files like activites, homework and worksheet.
To add resources, you must be the owner of the Modality. Click Customize to make your own copy.

# Reviews

Please wait...
Please wait...
Image Detail
Sizes: Medium | Original