7th Grade Math

Get ConnectED

Rates and Functions

PART A B CDE

Multi-Part

Lesson 1

GLE 0706.3.2

Understand and compare

various representations of

relations and functions.

GLE 0706.3.3 Understand

the concept of function as a

rule that assigns to a given

input one and only one

number (the output). Also

addresses GLE 0706.3.4,

SPI 0706.3.3, SPI 0706.3.5.

378 Linear Functions

Main Idea

Make function tables

and write equations.

Vocabulary

relation

function

function rule

function table

domain

range

independent variable

dependent variable

function notation

Equations and Functions

MAGAZINES Suppose you

Number Multiply by 4 Cost ($)

1

2

3

4

4 × 1 4

can buy magazines for

$4 each.

1. Copy and complete the
   table to find the cost of
   2, 3, and 4 magazines.


2. Describe the pattern in the
   table between the cost and
   the number of magazines.

A relation is a set of ordered pairs. A function is a relation in which

each member of the input is paired with exactly one member of the

output. A function rule is the operation(s) performed on the input

value to get the output value.

Input Function Output

Rule

You can organize the input numbers, output numbers, and the

function rule in a function table. The set of input values is called the

domain, and the set of output values is called the range.

Make a Function Table

MONEY Javier saves $20 each Input Function Rule Output

Number of

Months

Multiply by

20

Total

Savings ($)

1 20 × 120

2 20 × 240

3 20 × 360

4 20 × 480

month. Make a function

table to show his savings

after 1, 2, 3, and 4 months.

Then identify the domain

and range.

The domain is {1, 2, 3, 4}, and

the range is {20, 40, 60, 80}.

a. MOVIES A student movie ticket costs $3. Make a function table

that shows the total cost for 1, 2, 3, and 4 tickets. Then identify

the domain and range.

V

r

canb

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