Lesson 4-2 Pages 153-157

Powers and Exponents

Lesson Check 4-1

What you will learn!1. How to write expressions using exponents.

2. How to evaluate expressions containing exponents.

BaseBase

ExponentExponent

PowerPower

Standard formStandard form

Expanded formExpanded form

What you really need to know!

A number that is expressed using an exponent is called a power. The exponent tells you how many times to use the base as a factor.

34 = 3 x 3 x 3 x 3

What you really need to know!

Expressions involving powers are evaluated using order of operations. Powers are evaluated after any grouping symbols and before other multiplication or division operations.

Example 1:

Write each expressions using exponents.

6•6•6•6 = 64

Example 2:

Write each expressions using exponents.

p = p1

Example 3:

Write each expressions using exponents.

(-1)(-1)(-1) = (-1)3

Example 4:

Write each expressions using exponents.

(5x + 1)(5x + 1)

(5x + 1)2

Example 5:

Write each expressions using exponents.

yyyxxxx 21

3421 yx

Example 6:

Express 235,016 in expanded form.

(2 x 105) + (3 x 104)

+ (5 x 103) + (0 x 102)

+ (1 x 101) + (6 x 100)

Example 7:

42

Evaluate each expression.

= 4•4 = 16

Example 8:

r3 – 3 if r = -2Evaluate each expression.

(-2)3 – 3-8 – 3

-11

Example 9:

x(y + 2)2 if x = 2 and y = -2

2(-2 + 2)2

2(0)2

2(0)0

Page 155

Guided Practice

#’s 4-11

Pages 153-155 with someone at home and study

examples!

Read:

Homework: Pages 155-157

#’s 12-56 even

#’s 60-75

Lesson Check 4-2

Page

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Lesson 4-2

Lesson Check 4-2