Uploaded by Jonathan Barnes

Absolute Value Functions

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Unit 6 Alg 1
Name:_________________________
Period:______
Unit 6 Note Packet
List of topics for this unit/Assignment tracker
Topic
Assignment & Due Date
Date
Graphing Absolute Value Equations Part 1
Graphing Absolute Value Equations Part 2
OC 6.2 Translating the Graph of 𝑓 𝑥 = 𝑥
Quiz 1
OC 6.3 Stretching, Shrinking, and Reflecting the Graph
of 𝑓 𝑥 = 𝑥
OC 6.4 Combining Transformations of the Graph of
𝑓 𝑥 = 𝑥
Quiz 2
6.5 Solve Absolute Value Equations
OC 6.5 Solving Absolute Value Equations
Quiz 3
Review
Test
This packet is due for 100 points on the day of the test. 10 points will be deducted for each section of
notes that is missing. 5 points will be deducted for each warm up that is missing. If you’re absent,
get the notes and warm up from me or a classmate.
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Unit 6 Alg 1
Graphing Absolute Value Equations Part 1
Date:
WARM UP
Graph each.
𝟏
1. 𝒚 = 𝟑 𝒙 − 𝟐
3. 𝒙 = 𝟑
2. 𝟐𝒙 + 𝟑𝒚 = 𝟔
Review Vocabulary
Absolute Value
Guided Practice
Simplify.
1. −10
2. 12 − 19
3. 20 − 8
Your Turn
4. 4.5
5. 9 ∙ −5
6. − 17
Guided Practice
7. Graph 𝑦 = 𝑥
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Unit 6 Alg 1
8. Graph 𝑦 = 3𝑥
Your Turn
9. Graph 𝑦 =
1
2
𝑥
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Unit 6 Alg 1
Guided Practice
10. Graph 𝑦 = 𝑥 − 5
Your Turn
11. Graph 𝑦 = 𝑥 + 4
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Unit 6 Alg 1
𝟏. 𝒚 = 𝟒𝒙
𝟒. 𝒚 = 𝒙 − 𝟔
Graphing Absolute Value Equations Part 1 Assignment
2. 𝒚 = −𝒙
𝟑. 𝒚 = −𝟑𝒙
5. 𝒚 = 𝒙 + 𝟐
𝟔. 𝒚 = 𝒙 − 𝟑
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Unit 6 Alg 1
Graphing Absolute Value Equations Part 2
WARM UP
Graph each.
1. y = x + 1
Date:
2. 𝑦 = 2𝑥
Graphing Absolute Value Functions
𝒚=𝒂 𝒙−𝒉 +𝒌
How a changes the graph:
How h changes the graph:
How k changes the graph:
Guided Practice
1. Graph 𝑦 = − 𝑥 + 2 + 3
x
y
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Unit 6 Alg 1
2. Graph 𝑦 = 2 𝑥 + 6 − 5
Your Turn
3. Graph 𝑦 = − 𝑥 + 3 − 4
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Guided Practice
Write an equation of the graph.
4.
5.
Your Turn
6.
7.
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Unit 6 Alg 1
𝟏. 𝒚 = 𝟔 𝒙 − 𝟕
Graphing Absolute Value Equations Part 2 Assignment
2. 𝒚 = 𝒙 + 𝟗
𝟑. 𝒚 = − 𝒙 − 𝟖 + 𝟏
𝟒. 𝒚 = − 𝒙 + 𝟐 + 𝟏𝟏
5. 𝒚 = 𝟐 𝒙 + 𝟐 + 𝟑
𝟔. 𝒚 = 𝟑 𝒙 − 𝟏 − 𝟑
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Unit 6 Alg 1
OC 6.2 Translating the Graph of 𝒇 𝒙 = 𝒙
WARM UP
Graph each.
1. y = x + 1
Date:
2. y = x − 1 − 3
1 ENGAGE Understanding the Parent Absolute Value Function
The most basic absolute value function is a given by the following rule.
f(x) = |x|
This function is sometimes called the parent absolute
value function.
To graph the function, you can make a table of values
like the one shown, plot the ordered pairs, and draw
the graph.
As shown at the right, the function's V-shaped graph
consists of two rays with a common endpoint at (0, 0). This point is
called the vertex of the graph.
REFLECT
1a. What is the domain of f(x) = |x|? What is the range?
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_____________
1b. If you fold the graph of f(x) = |x| over the y-axis, the two halves of the graph match up perfectly. The graph
is said to be symmetric about the y-axis. Explain why it makes sense that the graph of f(x) = |x| is symmetric
about the y-axis.
___________________
1b. For what values of x is the function f(x) = |x| increasing? decreasing?
__________________
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Unit 6 Alg 1
2 EXAMPLE Graphing Functions of the Form g(x) = |x − h| + k
Graph each absolute value function. (The graph of the parent function f(x) = |x| is shown in gray.)
A g(x) = |x| + 2
B g(x) = |x − 4|
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Unit 6 Alg 1
C g(x) = |x − 4| + 2
REFLECT
2a. How is the graph of g (x) = |x| + 2 related to the graph of the parent function f(x) = |x|?
___________________
2b. How do you think the graph of g(x) = |x| − 2 would be related to the graph of the parent function f(x) =
|x|?
___________________
2c. How is the graph of g(x) = |x − 4| related to the graph of the parent function f(x) = |x|?
________________
2d. How do you think the graph of g(x) = |x + 4| would be related to the graph of the parent function f(x) =
|x|?
________________
2e. How is the graph of g(x) = |x − 4| + 2 related to the graph of the parent function f(x) = |x|?
___________________
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2f. Predict how the graph of g(x) = |x + 3| − 5 is related to the graph of the parent function f(x) = |x|. Then
check your prediction by making a table of values and graphing the function. (The graph of f(x) = |x| is
shown in gray.)
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Unit 6 Alg 1
2g. In general, how is the graph of g(x) = |x − h| + k related to the graph of f(x) = |x|?
___________________
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EXAMPLE Writing Equations for Absolute Value
Functions
Write the equation for the absolute value function whose graph is
shown.
A Compare the given graph to the graph of the parent function f(x) = |x|.
Complete the table to describe how the parent function must be translated
to get the graph shown here.
B Determine the values of h and k for the function g(x) = |x − h| + k.
•h is the number of units that the parent function is translated horizontally. For a translation to the
right, h is positive; for a translation to the left, h is negative.
•k is the number of units that the parent function is translated vertically. For a translation up, k is
positive; for a translation down, k is negative.
So, h =
and k =
. The function is
.
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Unit 6 Alg 1
REFLECT
3a. What can you do to check that your equation is correct?
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___________________
3b. If the graph of an absolute value function is a translation of the graph of the parent function, explain
how you can use the vertex of the translated graph to help you determine the equation for the function.
___________________
___________________
3c. Suppose the graph in the Example is shifted left one unit so that the vertex is at (1, 3). What will be the
equation of that absolute value function?
___________________
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Unit 6 Alg 1
OC 6.2 Translating the Graph of 𝒇 𝒙 = 𝒙 Assignment
Graph each absolute value function.
Write the equation of each absolute value function whose graph is shown.
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Unit 6 Alg 1
OC 6.3 Stretching, Shrinking, and Reflecting the Graph of 𝒇 𝒙 = 𝒙
Date:
WARM UP
Graph each.
1. y = x + 2 − 5
2. y = x − 3 + 1
1 EXAMPLE Graphing g(x) = a|x| when |a| > 1
Graph each absolute value function using the same coordinate plane. (The graph of the parent
function f(x) = |x| is shown in gray.)
A g(x) = 2|x|
B g(x) = –2|x|
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Unit 6 Alg 1
REFLECT
1a. The graph of the parent function f(x) = |x| includes the point (–1, 1) because f(−1) = |–1| = 1. The
corresponding point on the graph of g(x) = 2|x| is (–1, 2) because g(–1) = 2|–1| = 2. In general, how does the
y-coordinate of a point on the graph of g(x) = 2|x| compare with the y-coordinate of a point on the graph of
f(x) = |x| when the points have the same x-coordinate?
______________________
1b. Describe how the graph of g(x) = 2|x| compares with the graph of f(x) = |x|. Use either the word stretch
or shrink, and include the direction of the movement.
1c.What other transformation occurs when the value of a in g(x) = a|x| is negative?
2 EXAMPLE Graphing g(x) = a|x| when |a| < 1
Graph each absolute value function using the same coordinate plane. (The graph of the parent
function f(x) = |x| is shown in gray.)
REFLECT
1
2a. How does the y-coordinate of a point on the graph of 𝑔 𝑥 = 4 𝑥 compare with the y-coordinate of a
point on the graph of f(x) = |x| when the points have the same x-coordinate?
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Unit 6 Alg 1
1
2b. Describe how the graph of 𝑔(𝑥) = 4 𝑥 compares with the graph of f(x) = |x|. Use either the word stretch
or shrink, and include the direction of the movement.
2c.What other transformation occurs when the value of a in g(x) = a|x| is negative?
2d. Compare the domain and range of g(x) = a|x| when a> 0 and when a< 0.
2e. Summarize your observations about the graph of g(x) = a|x|
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Unit 6 Alg 1
OC 6.3 Stretching, Shrinking, and Reflecting the Graph of 𝒇 𝒙 = 𝒙 Assignment
Graph each absolute value function.
Write the equation of each absolute value function whose graph is shown.
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Unit 6 Alg 1
OC 6.4 Combining Transformations of the Graph of 𝒇 𝒙 = 𝒙
Date:
WARM UP
Graph each.
1. y = 2 x − 1 − 2
1
2.y = − 2 x + 2 + 4
EXAMPLE Graphing g(x) = a|x− h| and g(x) = a|x| + k
Graph each absolute value function. (The graph of the parent function f(x) = |x| is shown in gray.)
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Unit 6 Alg 1
REFLECT
1
1a. How is the graph of 𝑔(𝑥) = 2 |𝑥 − 3| related to the graph of f(x) = |x|?
1b. How is the graph of g(x) = 3|x| − 7 related to the graph of f(x) = |x|?
1
1
1
1c. How is the graph of 𝑔(𝑥) = 2 |𝑥 − 3| affected if you replace 2 with − 2 and 3 with −3?
2 EXAMPLE Graphing g(x) = a|x − h| + k
Graph g(x) = −2|x + 1| + 3. (The graph of the parent
function f(x) = |x| is shown in gray.)
REFLECT
2a. How is the graph of g(x) = − 2|x + 1| + 3 related to the
graph of f(x) = |x|?
2b. How is the graph of g(x) = −2|x + 1| + 3 affected if you
replace 3 with −3?
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2c. Complete the table to summarize how you can obtain the graph of g(x) = a|x − h| + k from the graph of
the parent function f(x) = |x|.
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Unit 6 Alg 1
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Unit 6 Alg 1
OC 6.4 Combining Transformations of the Graph of 𝒇 𝒙 = 𝒙 Assignment
Graph each absolute value function.
Write the equation for each absolute value function whose graph is shown.
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6.5 Solve Absolute Value Equations
WARM UP
Graph each.
1. y = −2 x
Date:
1
2. y = − 2 x
Vocabulary
Absolute Value Equation
Guided Practice
1. Solve 𝑥 = 7
Your Turn
Solve
2. 𝑥 = −3
3. 𝑥 = 15
Solving an Absolute Value Equation
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Unit 6 Alg 1
Guided Practice
4. 𝑥 − 3 = 8
5.
4𝑥 − 5 = 18
Your Turn
6. 𝑟 − 7 = 9
7. 2𝑥 + 7 = 11
Guided Practice
8. 3 2𝑥 − 7 − 5 = 4
Your Turn
9. 2 𝑠 + 4.1 = 18.9
10. 4 𝑡 + 9 − 5 = 19
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Unit 6 Alg 1
Guided Practice
11. Solve 3𝑥 + 5 + 6 = −2 , if possible.
Your Turn
Solve the equation, if possible.
12. 2 𝑚 − 5 + 4 = 2
13. −3 𝑛 + 2 − 7 = −10
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Unit 6 Alg 1
6.5 Solve Absolute Value Equations Assignment
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Unit 6 Alg 1
OC 6.5 Solving Absolute Value Equations
Date:
WARM UP
1.
2.
1 EXAMPLE Solving an Absolute Value Equation by Graphing
Solve the equation 2|x − 3| + 1 = 5 by graphing.
A Treat the left side of the equation as the absolute value function f(x) = 2|x − 3| + 1. Graph the function by
following these steps.
• Identify and plot the vertex:
• If you move 1 unit to the left or right of the vertex, describe how must
you move vertically to get to a point on the graph. Give the coordinates of
these points and then plot them.
• Use the three plotted points to draw the complete graph.
B Treat the right side of the equation as the constant function g(x) = 5.
Draw the graph of g(x) on the same coordinate plane as the graph of f(x).
C Identify the x-coordinate of each point where the graphs of f(x) and g(x) intersect. Show that each xcoordinate is a solution of 2|x − 3| + 1 = 5.
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Unit 6 Alg 1
B Interpret the equation |x − 3| = 2: What numbers have an absolute value equal to 2?
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OC 6.5 Solving Absolute Value Equations Assignment
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Unit 6 Alg 1
Unit 6 Review
Date:
WARM UP
Solve. 1.
Examples
Evaluate each:
1. −6 + 1
2.
2. − −8 − 4 + 2
3. −2 −8 + 2 − 1
Graph by making a t-table.
4. 𝑦 = 𝑥 + 1 − 3
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Unit 6 Alg 1
Graph by using the translation and transformation methods.
2
5. 𝑦 = 𝑥 − 2 − 4
6. 𝑦 = 3 𝑥 − 5
7. 𝑦 = −3 𝑥 + 2 + 4
Solve each equation.
8.
9.
10.
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Unit 6 Alg 1
Unit 6 Review Assignment
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Unit 6 Alg 1
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