7th Grade Math

Expressions

PART A BCD

Multi-Part

Lesson 1

Get ConnectED

GLE 0706.2.5

Understand and work with

squares, cubes, square roots

and cube roots. SPI 0706.2.1

Simplify numerical

expressions involving rational

numbers. Also addresses

SPI 0706.2.3.

Lesson 1A Expressions 25

Powers and Exponents

TEXT MESSAGING

Minutes

Number of

Text Messages

0

1

2

3

1

1 × 2

2 × 2

2 × 2 × 2

= 1

= 2

= 4

= 8

Suppose you text one of

your friends. That friend

then texts two friends after

one minute. The pattern

continues.

1. How many text
   messages will be sent
   at 4 minutes?


2. What is the relationship
   between the number of
   2s and the number of
   minutes?

Two or more numbers that are multiplied together to form a product

are called factors. When the same factor is used, you may use an

exponent to simplify the notation. The exponent tells how many times

the base is used as a factor. The common factor is called the base.

Numbers expressed using exponents are called powers.

Powers Words

52 five to the second power or five squared

43 four to the third power or four cubed

24 two to the fourth power

Write Powers as Products

Write each power as a product of the same factor.

7 5 5 2

7 5 = 7 · 7 · 7 · 7 · 7 5 2 = 5 · 5

a. 6 4 b. 1 3 c. 2 5

S

Main Idea

Use powers and

exponents.

Vocabulary

factors

exponent

base

powers

squared

cubed

evaluate

standard form

exponential form

==···

base

exponent

V

f

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