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NAME _____________________________________________ DATE ____________________________ PERIOD _____________
Lesson 1 Reteach
Powers and Exponents
The product of repeated factors can be expressed as a power. A power consists of a base and an exponent. The
exponent tells how many times the base is used as a factor.
Example 1
Write each expression using exponents.
a. 7 • 7 • 7 • 7
7 • 7 • 7 • 7 = 74
The number 7 is a factor 4 times. So, 7 is the base and 4 is the exponent.
b. y • y • x • y • x
y•y•x•y•x=y•y•y•x•x
= (y • y • y) • (x • x)
= y3 • x2
Commutative Property
Associative Property
Definition of exponents
To evaluate a power, perform the repeated multiplication to find the product.
Example 2
Evaluate (–64).
(–6)4 = (–6) • (–6) • (–6) • (–6)
= 1,296
Write the power as a product.
Multiply.
The order of operations states that exponents are evaluated before multiplication, division, addition, and subtraction.
Example 3
Evaluate m2 + (n – m)3 if m = –3 and n = 2.
m2 + (n – m)3 = (–3)2 + (2 – (–3))3
2
= (–3) + (5)
3
Replace m with –3 and n with 2.
Perform operations inside parentheses.
= (–3 • –3) + (5 • 5 • 5)
Write the powers as products.
= 9 + 125 or 134
Add.
Lesson 2 Reteach
Multiply and Divide Monomials
The Product of Powers rule states that to multiply powers with the same base, add their exponents.
Example 1
Simplify. Express using exponents.
a. 𝟐𝟑 • 𝟐𝟐
b. 𝟐𝒔𝟔 (𝟕𝒔𝟕 )
23 • 22 = 23+2 The Common base
2.
= 25
Add the exponents.
2𝑠 6 (7𝑠 7 ) = (2 • 7)(s 6 • s 7 )
= 14(𝑠 6+7 )
Commutative and Associative Properties
The common base is s.
3
= 14𝑠
13
Add the exponents.
NAME _____________________________________________ DATE ____________________________ PERIOD _____________
The Quotient of Powers rule states that to divide powers with the same base, subtract their exponents.
Example 2
Simplify
𝒌𝟖
.
𝒌
Express using exponents.
𝑘8
𝑘1
= 𝑘 8−1 The common base is k.
= 𝑘7
Subtract the exponents.
Example 3
Simplify
(−𝟐)𝟏𝟎 • 𝟓𝟔 • 𝟔𝟖
(−𝟐)𝟔 • 𝟓𝟖 • 𝟔𝟐
(−2)10 • 56 • 68
(−2)6 • 58 • 62
.
(−2)10
)
(−2)6
= (
56
5
63
6
• ( 3) • ( 2)
Group by common base.
= (−2)4 • 53 • 61
Subtract the exponents.
= 16 • 125 • 6 or 12,000
Simplify.
Lesson 3 Reteach
Powers of Monomials
Power of a Power: To find the power of a power, multiply the exponents.
Power of a Product: To find the power of a product, find the power of each factor and multiply.
Example 1
Simplify (𝟓𝟑 )𝟔 .
(53 )6 = 53 • 6
Power of a power
= 518
Simplify.
Example 2
Simplify (−𝟑𝒎𝟐 𝒏𝟒 )𝟖 .
(−3𝑚2 𝑛4 )3 = (−3)3 • 𝑚2 • 3 • 𝑛4 • 3
6 12
= −27𝑚 𝑛
Power of a product
Simplify.
Lesson 4 Reteach
Negative Exponents
Any nonzero number to the zero power is 1. Any nonzero number to the negative n power is the multiplicative inverse of
the number to the nth power.
Example 1
3
NAME _____________________________________________ DATE ____________________________ PERIOD _____________
Write each expression using a positive exponent.
a. 𝟕−𝟑
1
7−3 = 73
b. 𝒂−𝟒
1
𝑎−4 = 𝑎3
Definition of negative exponent
Definition of negative exponent
Example 2
Evaluate each expression.
a. 𝟓−𝟒
1
5−4 = 54
=
1
625
b. (−𝟑)−𝟓
1
(−3)−5 = (−3)5
Definition of negative exponent
=
54 = 5 • 5 • 5 • 5
1
−243
Definition of negative exponent
(–3)5 = (−3) • (−3) • (−3) • (−3) • (−3)
Example 3
𝟏
Write 𝟔𝟓 as an expression using a negative exponent.
1
65
= 6−5
Definition of negative exponent
Example 4
Simplify. Express using positive exponents.
𝒘−𝟓
a. 𝒙−𝟑 • 𝒙𝟓
b. 𝒘−𝟕
𝑥 −3 • 𝑥 5 = 𝑥 (−3)+5
= 𝑥2
Product of Powers
Add the exponents.
𝑤 −5
𝑤 −7
= 𝑤 −5−(−7)
= 𝑤2
Quotient of Powers
Subtract the exponents.
Lesson 5 Reteach
Scientific Notation
A number in scientific notation is written as the product of a factor that is at least one but less than ten and a power of
ten.
Example 1
Write 𝟖. 𝟔𝟓 × 𝟏𝟎𝟕 in standard form.
8.65 × 107 = 8.65 × 10,000,000
= 86,500,000
107= 10 • 10 • 10 • 10 • 10 • 10 • 10 or 10,000,000
The decimal point moves 7 places to the right.
Example 2
Write 𝟗. 𝟐 × 𝟏𝟎−𝟑 in standard form.
9.2 × 10−3 = 9.2 × 0.001
The decimal point moves 3 places to the left.
= 0.0092
Example 3
Write 76,250 in scientific notation.
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NAME _____________________________________________ DATE ____________________________ PERIOD _____________
76,250 = 7.625 × 10,000
The decimal point moves 4 places.
= 7.625 × 104
Since 76,250 is >1, the exponent is positive.
Example 4
Write 0.00157 in scientific notation.
0.00157 = 1.57 × 0.001
The decimal point moves 3 places.
= 1.57 × 10−3
Since 0.00157 is <1, the exponent is negative.
Lesson 6 Reteach
Compute with Scientific Notation
You can use the Product of Powers and Quotient of Powers properties to multiply and divide numbers written in
scientific notation.
Example 1
Evaluate (𝟑. 𝟒 × 𝟏𝟎𝟓 )(𝟐. 𝟑 × 𝟏𝟎𝟑 ). Express the result in scientific notation.
(3.4 × 105 )(2.3 × 103 ) = (3.4 × 2.3)(105 × 103 )
= (7.82)(105 × 103 )
= 7.82 × 10
5+3
Commutative and Associative Properties
Multiply 3.4 by 2.3.
Product of Powers
= 7.82 × 108
Add the exponents.
Example 2
Evaluate
2.325 × 104
3.1 × 104
𝟐.𝟑𝟐𝟓 × 𝟏𝟎𝟒
𝟑.𝟏 × 𝟏𝟎𝟒
. Express the result in scientific notation.
2.325
104
)
(
)
3.1
102
=(
104
Associative Property
= (0.75) (102 )
Divide 2.325 by 3.1.
= 0.75 × 104−2
Quotient of Powers
= 0.75 × 10
2
Subtract the exponents.
= 0.75 × 102
Write 0.75 × 102 in scientific notation.
= 7.5 × 10
Since the decimal point moved 1 place to the right, subtract 1 from the exponent.
Example 3
Evaluate (𝟓. 𝟐𝟒 × 𝟏𝟎𝟓 ) + (𝟖. 𝟔𝟓 × 𝟏𝟎𝟔 ). Express the result in scientific notation.
(5.24 × 105 ) + (8.65 × 106 ) = (5.24 × 105 ) + (86.5 × 105 )
= (5.24 + 86.5) × 105
= 91.74 × 10
5
= 9.174 × 106
Write 8.65 × 106 as 86.5 × 105.
Distributive Property
Add 5.24 and 86.5.
Write 91.74 × 105 in scientific notation.
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