Name ________________________________________ Date __________________ Class__________________
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1-6 Holt Algebra 2
Reteach Sets of Numbers
As you move from left to right on a number line, the numbers increase. Use a number line to help you order real numbers. Order from least to greatest:
111, 2.6, , , 2.354.2 2
π− −
Use a calculator to approximate 11 and 2π− as decimals:
11 ≈ 3.32 and 2π− ≈ −1.57.
Plot each point on a number line.
Read the numbers from left to right on the number line.
From least to greatest, the order is 12.6, , , 2.354, 11.2 2π− −
Order the given numbers from least to greatest. Use a number line to help you.
1. π, 1.9− , 223
, −0.456, and 3
π ≈ 3.14, 223
≈ 2.67, and 3 ≈ 1.73
____________________________
2. −1.75, 1, 15
, 1.55, and 5−
15
= ____________
5− ≈ ____________
____________________________
3. 6, 2.63, 4.36, 2 3,− − and 16
−
6 ≈ ____________
2 3 ≈ ____________
16
− ≈ ____________
____________________________
LESSON
1-1
Name ________________________________________ Date __________________ Class__________________
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1-7 Holt Algebra 2
Reteach Sets of Numbers (continued)
You can represent the same set in different ways.
Number line: Words: The set of numbers greater than or equal to −2 and less than 0 OR greater than or equal to 1 Interval Notation: [−2, 0) or [1, ∞) Set-Builder Notation: {x | −2 ≤ x < 0 or x ≥ 1} This set cannot be described in roster notation because you cannot list the real numbers in the intervals shown on the number line. The roster notation of , the set of natural numbers, is {1, 2, 3, ...}. The set-builder notation of is {x|x ∈ }.
Rewrite each set using the indicated notation. 4. the set of integers, or ; roster notation {…, −3, −2,_______________________________} 5. {0, 4, 8, 12, 16, …}; words ______________________________ 6. −5 ≤ x ≤ 12; interval notation [ _______________________________ 7. {x|x < 0}; interval notation (−∞ _______________________________ 8.
set-builder notation {x| _______________________________
LESSON
1-1
∞ means infinity and –∞ means negative infinity.
Brackets [ ] include the endpoints. Parentheses ( ) do not include endpoints.
Read this as “x such that”
Name ________________________________________ Date __________________ Class__________________
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1-14 Holt Algebra 2
Reteach Properties of Real Numbers
Find the additive inverse of each number. 1. 20 2. –36 3. –7.9 20 + ( ________ ) = 0 –36 + ( ________ ) = 0 –7.9 + ( ________ ) = 0
4. 23
5. 3 6. 34
−
________________________ _________________________ ________________________
Identify the property of addition demonstrated by each equation.
7. x + 0 = x _____________________________
8. (2 + m) + 5n = 2 + (m + 5n) _____________________________
9. 4r + 6s = 6s + 4r _____________________________
10. π + (−π) = 0 _____________________________
11. c + (−2) = −2 + c _____________________________
12. 1 = 0 + 1 _____________________________
LESSON
1-2
Properties of Addition Examples
Additive Identity 0 is the additive identity.
4 + 0 = 4 n + 0 = 0 + n = n
Additive Inverse The sum of a number and its opposite is 0.
8 + (–8) = 0 n + (–n) = 0
Closure Property The sum of any two real numbers is a real number.
3 + 5 = 8 a + b ∈
Commutative Property The order does not change the sum.
6 + 12 = 12 + 6 a + b = b + a
Associative Property The grouping does not change the sum.
(2 + 5) + 9 = 2 + (9 + 5) (a + b) + c = a + (b + c)
The additive inverse of 8 is –8.The additive inverse of –8 is 8.
Name ________________________________________ Date __________________ Class__________________
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1-15 Holt Algebra 2
Reteach Properties of Real Numbers (continued)
Find the multiplicative inverse of each number.
13. 25 14. 35
− 15. 18
−
25 ⋅ ( ________ ) = 1 35
− ⋅ ( ________ ) = 1 18
− ⋅ ( ________ ) = 1
16. 13
17. −4 18. π
________________________ _________________________ ________________________
IIdentify the property of multiplication demonstrated by each equation.
19. 6(2x + y) = 6(2x) + 6y _________________________
20. 9(4.2) = (4.2)9 _________________________
21. 4(3 10) (4 3) 10= i _________________________
LESSON
1-2
Properties of Multiplication Examples
Multiplicative Identity 1 is the multiplicative identity. −12 ⋅ 1 = −12
n ⋅ 1 = 1 ⋅ n = n
Multiplicative Inverse The product of a number and its reciprocal is 1.
2 3 13 2
⎛ ⎞− − =⎜ ⎟⎝ ⎠i
1 1, 0n nn
= ≠i
Closure Property The product of any two real numbers is a real number.
8(−0.5) = −4 ab ∈
Commutative Property The order does not change the product.
1 13 (3)6 6
⎛ ⎞ =⎜ ⎟⎝ ⎠
ab = ba
Associative Property The grouping does not change the product.
(3 ⋅ 7)4 = 3(7 ⋅ 4) (ab)c = a(bc)
Distributive Property −2(4 + 7) = −2(4) + (−2)(7) a(b + c) = ab + ac
The multiplicative inverse
of 23
− is 32
− .
Name ________________________________________ Date __________________ Class__________________
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1-22 Holt Algebra 2
Reteach Square Roots
Use properties of square roots to simplify expressions with square roots.
Product Property: for a > 0 and b > 0, ab a b= i
200 100 2 100 2 10 2= = =i 27 3 27 3 81 9= = =i i
Quotient Property: for a > 0 and b > 0, a ab b
=
25 25 549 749
= = 108 108 36 633
= = =
Simplify each expression.
1. 20 2. 63 3. 80
4 5i 9 ________i 16 ________i
4 ________i 9 ________i 16 ________i
________________________ _________________________ ________________________
4. 3 12i 5. 6425
6. 2008
________ ________i ________________
________________
________________________ _________________________ ________________________
7. 6 24i 8. 4487
9. 49100
________________________ _________________________ ________________________
LESSON
1-3
Multiply under the radical. Look for a perfect square factor.
Evaluate perfect square factors. Divide under the radical.
Name ________________________________________ Date __________________ Class__________________
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1-23 Holt Algebra 2
Reteach Square Roots (continued)
Rationalize the denominator to eliminate radicals from the denominator.
3 5 23 5 3 5 2 3 102 22 2 2
= = =i
i
Combine like radical terms to add or subtract square roots.
3 2 8+
3 2 4 2+ ⋅
3 2 2 2+
(3 2) 2+
5 2
Simplify by rationalizing each denominator.
10. 45
11. 16
12. 3 28
4 55 5i 1 ________
6i 3 2 ________
8i
________________________ _________________________ ________________________
Add or subtract.
13. 12 7 4 7− 14. 75 27− 15. 6 5 45+
(12 4) 7− 25 3 9 3−i i 6 5 ________+
________________________ _________________________ ________________________
LESSON
1-3
Multiply by 1: 2 12
= Think: 2 2 2⋅ =
Try to use 2 as a factor.
Both terms contain 2 . Combine like terms.
Name ________________________________________ Date __________________ Class__________________
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1-30 Holt Algebra 2
Reteach Simplifying Algebraic Expressions
To evaluate an algebraic expression you substitute numbers for variables. Then follow the order of operations. Here is a sentence that can help you remember the order of operations. Evaluate x − 2xy + y2 for x = 4 and y = 6. 4 − 2(4)(6) + (6)2 Substitute 4 for x and 6 for y. 4 − 2(4)(6) + 36 Evaluate exponents: 62 = 36. 4 − 48 + 36 Multiply from left to right. −8 Add and subtract from left to right.
Evaluate each expression for the given values of the variables.
1. a2 + 2ab2 − 3a for a = 5 and b = 2
52 + 2(5)(2)2 − _______________ Substitute 5 for a and 2 for b.
25 + _______________________ Evaluate exponents.
___________________________ Multiply from left to right.
___________________________ Add and subtract from left to right.
2. c2 − cd + 3d for c = 7 and d = 6
___________________________ Substitute for the variables.
___________________________ Evaluate exponents.
___________________________ Multiply from left to right.
___________________________ Add and subtract from left to right.
3. 3(5 )
3m n
n− for m = 4 and n = 2
___________________________ Substitute for the variables.
___________________________ Evaluate exponents inside parentheses.
___________________________ Multiply inside parentheses.
___________________________ Subtract inside parentheses.
___________________________ Multiply from left to right.
___________________________ Divide from left to right.
Please Excuse My Dear Aunt Sally
Parentheses Exponents Multiply Divide Add Subtract
LESSON
1-4
Name ________________________________________ Date __________________ Class__________________
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1-31 Holt Algebra 2
Reteach Simplifying Algebraic Expressions (continued)
Add or subtract the coefficients of like terms to simplify an algebraic expression.
Like Terms: 3x2 and 4x2 5xy and −xy 3x2 + 5xy + 4x2 − xy + 2 3x2 + 4x2 + 5xy − xy + 2 Group like terms. 7x2 + 4xy + 2 Add or subtract like terms.
You can use the Distributive Property to simplify an algebraic expression. −2(a2 − ab) + 6ab + 2a2 −2a2 + 2ab + 6ab + 2a2 Distribute. −2a2 + 2a2 + 2ab + 6ab Group like terms. 8ab Add or subtract like terms.
Simplify each expression.
4. −6x + 3 − 2x + 4x ________________________________ Group like terms.
________________________________ Add or subtract like terms.
5. c(4c + d ) − c2+ cd ________________________________ Distribute.
________________________________ Group like terms.
________________________________ Add or subtract like terms.
6. 4a2+ 5ab − 4a2− 2ab − 7 7. 3(s − 4t) + 3s − t
_________________________________________ ________________________________________
LESSON
1-4
Coefficients of x2 : 3 and 4 Coefficients of xy : 5 and −1
Think: 3x2 + 4x2 = 7x2
5xy − 1xy = 4xy
−2(a2 − ab) = −2(a2) − 2(−ab) = −2a2 + 2ab
Think: −2a2 + 2a2 = 0
Name ________________________________________ Date __________________ Class__________________
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1-38 Holt Algebra 2
Reteach Properties of Exponents
−4x5 = −4(x ⋅ x ⋅ x ⋅ x ⋅ x) −(4x5) = −(4x)(4x)(4x)(4x)(4x) (−4x)5 = (−4x)(−4x)(−4x)(−4x)(−4x) 4x3(y + 6)2 = 4(x)(x)(x)(y + 6)(y + 6)
Zero Exponent Property: a0 = 1; a is not zero 380 = 1
Negative Exponent Property: 1nna
a− = and ;
n na bb a
−⎛ ⎞ ⎛ ⎞=⎜ ⎟ ⎜ ⎟⎝ ⎠ ⎝ ⎠
a is not zero.
44
1 1 133 3 3 3 813
− = = =i i i
3 32 5 5 5 5 1255 2 2 2 2 8
−⎛ ⎞ ⎛ ⎞= = =⎜ ⎟ ⎜ ⎟⎝ ⎠ ⎝ ⎠
i i
Write each expression in expanded form. 1. −8c3 2. (3xy)4 3. a3(b − c)2
−8(c ⋅ __________) ___________________ ____________________
Evaluate each expression. 4. 6−1 5. 100 6. 12−2
________________________ _________________________ ________________________
7. (−4)−3 8. 21
7
−⎛ ⎞⎜ ⎟⎝ ⎠
9. 33
4
−⎛ ⎞⎜ ⎟⎝ ⎠
________________________ _________________________ ________________________
10. −50 11. 22
5−⎛ ⎞
⎜ ⎟⎝ ⎠
12. 21
3
−⎛ ⎞− ⎜ ⎟⎝ ⎠
________________________ _________________________ ________________________
LESSON
1-5
Write
Expanded Form Exponent FormRead
a ⋅ a a2 a squared
a ⋅ a ⋅ a a3 a cubed
a ⋅ a ⋅ a ⋅ a a4 a to the fourth power
a ⋅ a ⋅ … ⋅ a an a to the nth power
List the factors to expand exponential expressions.
Name ________________________________________ Date __________________ Class__________________
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1-39 Holt Algebra 2
Reteach Properties of Exponents (continued)
Properties of Exponents (m and n are integers; a and b are nonzero real numbers.)
Same Base: am ⋅ an = am + n m
naa
= am − n (am)n = am n
Different Bases: (ab)m = ambm
m m
ma ab b
⎛ ⎞ =⎜ ⎟⎝ ⎠
Combine properties of exponents to simplify expressions with exponents. (2x5)4 c4d(c−3d
2) 24(x5)4 Distribute the exponent. c4c−3dd
2 Group like variables. 24x5 ⋅ 4 Multiply exponents. c4−3d1+2 Add exponents. 24x20 Simplify. cd3 Simplify. 16x20
5
4 33rsr s
3r1−4s5−3 Subtract exponents. 3r−3s2 Simplify.
2
33sr
Record answer with positive exponents.
Simplify each expression. Assume all variables are nonzero. 13. (−5ab3)2 14. w2x5(w4 x3) 15. y4z3(y−1z)2 (−5)2a2b3 2 w2+4x5+3 y4y−2z3z2
________________________ _________________________ ________________________
16.3
263
s tst
17. 34
2ab
⎛ ⎞⎜ ⎟⎝ ⎠
18. −3x−2y3(9x−1y5)
3 1 1 263
s t− − 4 3
2 3ab
i
i −3(9)x−2−1y3+5
________________________ _________________________ ________________________
LESSON
1-5
To multiply, add exponents.
To divide, subtract exponents.
To raise to a power, multiply exponents.
Distribute the exponent.
Name ________________________________________ Date __________________ Class__________________
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1-46 Holt Algebra 2
Reteach Relations and Functions
A relation pairs input values (x) and output values (y).
List domain and range elements from least to greatest.
Domain: {1996, 1998, 2000, 2002, 2004} Set of x-coordinates Range: {56, 82, 95, 136, 212} Set of y-coordinates The domain of a set of ordered pairs is the x-coordinates. The range is the y-coordinates. Each value is listed only once. For the graph at right: Domain: {−4, −2, 0, 2, 4}; Range: {0, 2, 3}
Give the domain and range for each relation. 1.
Domain: {2001, ______________________ Range: {25, ______________________
2. Domain: {−4, ____________________
Range: {−2, ____________________
LESSON
1-6
Domain Set of input values or x-coordinates
Range Set of output values or y-coordinates
Soccer Registration
Year 1996 1998 2000 2002 2004
Number of Players 56 82 95 136 212
Concert Ticket Price
Year 2001 2002 2003 2004 2005
Price ($) 25 28 35 42 46
Name ________________________________________ Date __________________ Class__________________
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1-47 Holt Algebra 2
Reteach Relations and Functions (continued)
A function is a special type of relation. A function has only one output for each input.
Use the vertical-line test to decide whether a relation is a function.
Use the vertical-line test to determine whether each relation is a function. If not, identify two points a vertical line would pass through.
3.
4.
_________________________________________ ________________________________________
LESSON
1-6
Draw a vertical line. The line passes through no more than one point on the graph. This is a function.
Draw a vertical line. The line passes through two points on the graph, at (1, −1) and (1, 1). This is not a function.
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1-54 Holt Algebra 2
Reteach Function Notation
You can use function notation to write a function.
f(x) = 2x − 3
Evaluate f(0), 12
f ⎛ ⎞⎜ ⎟⎝ ⎠
, and f(−2) for f(x) = 2x2− x + 1.
f(0) = 2(0)2 − 0 + 1 = 1 21 1 1 1 1 1 12 1 2 1 1 1
2 2 2 4 2 2 2f ⎛ ⎞ ⎛ ⎞ ⎛ ⎞= − + = − + = − + =⎜ ⎟ ⎜ ⎟ ⎜ ⎟⎝ ⎠ ⎝ ⎠ ⎝ ⎠
f (−2) = 2(−2)2 − (−2) + 1 = 2(4) + 2 + 1 = 8 + 2 + 1 = 11
For each function, evaluate f (0), ⎛ ⎞⎜ ⎟⎝ ⎠
32
f , and f (−1).
1. f (x) = 4x2 − 2
f (0) = 4(0)2 − 2 23 34 2
2 2f ⎛ ⎞ ⎛ ⎞= −⎜ ⎟ ⎜ ⎟⎝ ⎠ ⎝ ⎠
f (−1) = 4(−1)2− 2
________________________ _________________________ ________________________
2. f (x) = −2x + 10
f (0) = ______________ 32
f ⎛ ⎞⎜ ⎟⎝ ⎠
= ____________ f (−1) = ______________
3. f (x) = x2+ 6x
f (0) = ______________ 32
f ⎛ ⎞⎜ ⎟⎝ ⎠
= ____________ f (−1) = ______________
LESSON
1-7
Read: f of x equals 2x − 3.
Output f(x) Input x
Subsitute 0 for x in the function and evaluate.
Substitute 12
for x.
Substitute −2 for x.
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1-55 Holt Algebra 2
Reteach Function Notation (continued)
Plot ordered pairs on a coordinate plane to graph a function.
To graph f (x) = −2x + 3, make a table of values.
Graph each function on the coordinate plane given.
4.
5. g(x) = 2x − 4
x 2x − 4 g (x)
0
1
2
3
4
LESSON
1-7
Values between given points are not defined. Do not connect the points.
x −2x + 3 f (x)
−2 −2(−2) + 3 7
−1 −2(−1) + 3 5
0 −2(0) + 3 3
1 −2(1) + 3 1
2 −2(2) + 3 −1
All points are defined. Connect the points.
Name ________________________________________ Date __________________ Class__________________
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1-62 Holt Algebra 2
Reteach Exploring Transformations
A translation moves a point, figure, or function right, left, up, or down. Translate the function y = f (x) left 2 units.
A reflection flips a point, figure, or function across a line. Reflect the function y = f (x) across the x-axis.
Perform each transformation of y = f (x). 1. translation up 2 units 2. reflection across x-axis
LESSON
1-8
Horizontal Translation (right or left) Vertical Translation (up or down)
The x-coordinate changes. (x, y) → (x + h, y)
The y-coordinate changes. (x, y) → (x, y + k)
Move each point 2 units left. Connect the points. (x, y ) → (x − 2, y)
Reflection Across y-axis Reflection Across x-axis
The x-coordinate changes. (x, y ) → (−x, y)
The y-coordinate changes. (x, y ) → (x, −y)
Flip each point across the axis. Connect the points. (x, y ) → (x, −y)
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1-63 Holt Algebra 2
Reteach Exploring Transformations (continued)
In a stretch or a compression, the new figure has a different shape than the original. Perform a vertical stretch of the function y = f (x) by a factor of 2. In a vertical stretch (x, y) → (x, ay). In this case, a = 2.
Perform each transformation of y = f (x).
3. horizontal stretch by a factor of 2 4. vertical compression by a factor of 12
LESSON
1-8
Horizontal Stretch (away from y-axis)
The x-coordinate changes. (x, y) → (bx, y); | b | > 1
Vertical Stretch (away from x-axis)
The y-coordinate changes. (x, y) → (x, ay); | a | > 1
Horizontal Compression (toward the y-axis)
The x-coordinate changes. (x, y) → (bx, y); 0 < | b | < 1
Vertical Compression (toward the x-axis)
The y-coordinate changes. (x, y) → (x, ay); 0 < | a | < 1
Original Figure (solid line)
x 2y Stretched Figure(dashed line)
(−3, 3) −3 6 (−3, 6)
(−1, 1) −1 2 (−1, 2)
(0, 2) 0 4 (0, 4)
(1, 1) 1 2 (1, 2)
(3, 3) 3 6 (3, 6)
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1-70 Holt Algebra 2
Reteach Introduction to Parent Functions
Functions can be classified into families. In the families, similar-looking functions represent transformations of a parent function. The parent function of g(x) = x3 − 1 is cubic. g(x) = x3 − 1 is a transformation from the parent function. It is a vertical translation 1 unit down.
Identify the parent function for g from its function rule. Then describe what transformation of the parent function it represents. 1. g(x) = −x2 2. ( ) 2g x x= +
Parent function ____________________ Parent function ____________________
________________________________ _________________________________
LESSON
1-9
Parent Functions
Linear f (x) = x
Quadratic f (x) = x2
Cubic f (x) = x3
Square Root ( )f x x=
x has a power of 3.
Compare the graph to the graph of the parent function.
Name ________________________________________ Date __________________ Class__________________
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1-71 Holt Algebra 2
Reteach Introduction to Parent Functions (continued)
You can graph data to identify a parent function.
The shape looks like the quadratic parent function f (x) = x2. It looks like a horizontal translation 2 units right.
Graph the data from each table. Describe the parent function and the transformation that best approximates the data set. 3. 4.
Parent function ____________________ Parent function ____________________
________________________________ _________________________________
________________________________ _________________________________
LESSON
1-9
x 2 1 3 0 4
y 0 1 1 4 4
Plot the points. Connect the points with a smooth curve. Compare shape to graphs of parent functions.
x −2 −1 0 1 2
y 1 −2 −3 −2 1
x −2 −1 0 1 2
y 2 1 0 −1 −2