LF3 LINEAR FUNCTIONS STUDENT PACKET 3: MULTIPLE REPRESENTATIONS 3
Transcription
LF3 LINEAR FUNCTIONS STUDENT PACKET 3: MULTIPLE REPRESENTATIONS 3
Name ___________________________ Period__________ Date ___________ LF3 uc e STUDENT PACKET od LINEAR FUNCTIONS STUDENT PACKET 3: MULTIPLE REPRESENTATIONS 3 Introduction to Functions • Define function. • Define the graph of a function • Explore and compare different representations of functions. • Determine when a set of ordered pairs is a graph of a function. 1 LF3.2 Best Buy Problems • Use different methods to determine the best buy, including tables and graphs. • Write equations that represent relationships between the numbers of an item purchased and the cost of the purchase. • Define and identify direct proportion functions. • Identify unit rates from equations and graphs. 7 pl e: D o N ot R ep r LF3.1 Rate Graphs • Solve problems involving rates, average speed, distance, and time. • Represent situations graphically and interpret the meaning of specific parts of a graph. 12 LFN3.4 Vocabulary, Skill Builders, and Review 18 Sa m LF3.3 Linear Functions Unit (Student Packet) LF3 – SP Multiple Representations 3 WORD BANK Definition or Explanation Example or Picture uc e Word or Phrase direct proportion ep r od function ot R graph of a function N input-output rule pl e: D rate o linear function m unit rate Sa variable Linear Functions Unit (Student Packet) LF3 – SP0 Multiple Representations 3 3.1 Introduction to Functions INTRODUCTION TO FUNCTIONS Set (Goals) Go (Warmup) od • Define function. • Define the graph of a function. • Explore and compare different representations of functions. • Determine when a set of ordered pairs is a graph of a function. ep r We will explore the concept of a function. We will define the terms function and the graph of a function. We will describe examples of functions and examples of non-functions. uc e Ready (Summary) N x x = y2 + 2 y 3 2 1 0 -1 -2 -3 Sa m pl e: D x 3 2 1 0 -1 -2 -3 2. y = x2 + 2 y o 1. ot R Fill in the t-tables and draw the graphs. All points may not fit on the grids. Linear Functions Unit (Student Packet) LF3 – SP1 Multiple Representations 3 3.1 Introduction to Functions WHAT IS A FUNCTION? uc e A function is a rule that assigns to each input value a unique output value. Example 1: Consider the equation y = x + 1. Here are some pairs of values that satisfy this equation. 4 5 3 4 2 3 1 2 0 1 -1 0 -2 -1 -3 -2 od x (input) y (output) Write the values in the table as ordered pairs (x, y). 2. For the input value x = 4, can y have a value other than 5? ______ 3. Do any of the given inputs have more than one output value? _______ 4. Can you think of any input values that might have more than one output value? _____ 5. Is the rule defined by the equation a function? _______ N ot R ep r 1. 7. Name of friend Number of pets Mary 3 Kerry 1 Larry 0 Barry 0 Can two (or more) different friends have the same number of pets? _______ Mary has 3 pets. Could Mary have exactly 3 pets and at the same time have exactly 7 pets?_______ m 8. Write the table as ordered pairs (input, output). . pl e: D 6. o Example 2: Here is a list of 4 friends (inputs) and the number of pets they own (outputs). Can any one friend have two different numbers of pets? _______ Sa 9. 10. Do the inputs and outputs in this table represent a function? _______ Linear Functions Unit (Student Packet) LF3 – SP2 Multiple Representations 3 3.1 Introduction to Functions WHAT IS A FUNCTION? (Continued) # of people in the apartment (output) od # of bedrooms in the apartment (input) 1 2 3 2 ot R 4 ep r 1 3 uc e Example 3: An apartment has building nine apartments. It has two one-bedroom apartments, four two-bedroom apartments, and three three-bedroom apartments. This mapping diagram shows the number of bedrooms and people in the apartments. 5 6 o N 11. Write the values in the mapping diagram as ordered pairs. pl e: D 12. How many apartments have 1 bedroom? _____ 2 bedrooms? _____ 3 bedrooms? _____ 13. How many apartments have 2 people living in it?______ 3 people living in it?______ 4 people living in it?______ m 1 person living in it?______ 6 people living in it?______ Sa 5 people living in it?______ 14. If you know the number of bedrooms in an apartment, can you determine the number of people that live in that apartment?_____ 15. Does this mapping diagram represent a function? _____ Linear Functions Unit (Student Packet) LF3 – SP3 Multiple Representations 3 3.1 Introduction to Functions PRACTICE WITH FUNCTIONS y 4 6 8 6 4 x 0 2 4 6 8 y 10 9 8 7 6 d. x 1 2 3 4 5 y 9 9 9 9 9 x 9 9 9 9 9 y 1 2 3 4 5 ep r x 0 3 6 9 12 c. od b. a. uc e 1. Which of the following input-output tables could illustrate functions if the variable x is used for the input value and y for the output value? ________________ 5. Which of the following sets of ordered pairs could illustrate functions? ______________ (10, 5), (10, 6), (10, 7), (10, 8) c. (0, 4), (1, 4), (2, 4), (3, 4) b. (1, 5), (2, 6), (3, 5), (4, 6) d. (10, -20), (-20, 10), (-10, -5), (10, 5) ot R a. a. 1 b. 2 8 3 6 6 5 c. -1 -3 3 m 1 -5 d. 1 -1 -3 3 5 -5 8 Sa 5 1 8 4 pl e: D 5 2 4 o 3 N 6. Which of the following mapping diagrams could illustrate functions? ________________ 7. Choose one example from above that is not a function and explain why. Linear Functions Unit (Student Packet) LF3 – SP4 Multiple Representations 3 3.1 Introduction to Functions THE GRAPH OF A FUNCTION uc e The graph of a function is its set of ordered pairs (x, y). For any point on the graph of a function, its x-coordinate will represent an input value and its y-coordinate will represent its corresponding output value. If the inputs and outputs are real numbers, then we can represent the graph of a function as points on the coordinate plane. od The vertical line test is a way to determine whether a set of ordered pairs in the usual xy-plane is the graph of a function. The vertical line test simply states that if a vertical line intersects a graph in more than one point, then it is a NOT a function. b. d. Sa m pl e: D c. o N ot R a. ep r 1. Use the vertical line test. Which of the following graphs could represent functions? 2. Try the vertical line test on the graphs you created in the warmup. Do these graphs represent functions? Explain. Linear Functions Unit (Student Packet) LF3 – SP5 Multiple Representations 3 3.1 Introduction to Functions DRAWING GRAPHS uc e Draw graphs to fit each description. 2. A nonlinear function (a function whose graph is not a line) 4. A nonlinear “non-function” (a graph that is not a line, and does not represent a function) m pl e: D o N 3. A linear “non-function” (a graph that is a line, and does not represent a function) ot R ep r od 1. A linear function (a function whose graph is a line) Sa 5. Explain why your graphs for problems 1 and 2 represent functions. 6. Explain why your graphs for problems 3 and 4 do not represent functions. Linear Functions Unit (Student Packet) LF3 – SP6 Multiple Representations 3 3.2 Best Buy Problems BEST BUY PROBLEMS Set (Goals) od • Use different methods to determine the best buy, including tables and graphs. • Write equations that represent relationships between the numbers of an item purchased and the cost of the purchase. • Define and identify direct proportion functions. • Identify unit rates from equations and graphs. ot R ep r We will use numbers and graphs to help determine which choices are better buys. We will learn about a special linear function called a direct proportion. uc e Ready (Summary) Go (Warmup) VALUE-MART N Suppose you are running out of your favorite pens and pencils, so you compare prices at two stores before making a purchase. pl e: D o Pens: 6 for $7.50 Pencils: 12 for $6.80 SAVINGS HUT Pens: 6 for $8.25 Pencils: 14 for $6.80 Sa m 1. At which store are pens cheaper? Explain. 2. At which store are pencils cheaper? Explain. Linear Functions Unit (Student Packet) LF3 – SP7 Multiple Representations 3 3.2 Best Buy Problems SHMEAR ‘N THINGS 4 bagels for $3.00 HOLE-Y BREAD 5 bagels for $4.00 5. Label and scale the grid. Graph the data using two different colors. 1. Complete the tables. Assume a proportional relationship. 5 8 10 12 15 16 20 20 25 ep r 4 od HOLE-Y BREAD # of cost bagels (y) (x) ot R SHMEAR ‘N THINGS # of cost bagels (y) (x) uc e BAGELS N 2. Which is the better buy? Use entries in the tables to explain your reasoning. o 6. Explain which graph illustrates a slower rise in price. pl e: D 3. Write equations to relate the number of bagels to cost. SHMEAR ‘N THINGS y = ________________ HOLE-Y BREAD y = ________________ m The linear functions you wrote above are both in the form y = mx. This is called a direct proportion equation because y is directly proportional to (is a multiple of) x. 7. Identify the coordinates when x = 1 SHMEAR ‘N THINGS (1, ____) HOLE-Y BREAD (1, ____) 8. What does this represent in the context of the problem? Sa 4. How is this equation different from the linear function y = mx + b? Linear Functions Unit (Student Packet) LF3 – SP8 Multiple Representations 3 3.2 Best Buy Problems FLAT ‘N ROUND 3 tortillas for $0.60 WRAP IT UP 4 tortillas for $1.00 6. Label and scale the grid. Graph the data using two different colors. 1. Complete the tables. Assume a proportional relationship # of tortillas (x) 4 6 8 cost (y) ot R 3 od WRAP IT UP ep r FLAT ‘N ROUND # of cost tortillas (y) (x) uc e TORTILLAS N 2. Which is the better buy? Use entries in the tables to explain your reasoning. o 7. Explain which graph illustrates a slower rise in price. pl e: D 3. Write equations to relate the number of tortillas to cost. FLAT ‘N ROUND y = ___________________ WRAP IT UP y = ___________________ 4. Identify the coordinates when x = 1 m FLAT ‘N ROUND WRAP IT UP (1, ____) (1, ____) Sa 5. How are these coordinates related to the unit rate for one tortilla? Linear Functions Unit (Student Packet) In the linear function y = mx + b, b represents the y-intercept. 8. Write coordinates for the y-intercepts for each function. FLAT ‘N ROUND (0, ____) WRAP IT UP (0, ____) 9. What does this represent in the context of the problem? LF3 – SP9 Multiple Representations 3 3.2 Best Buy Problems PAPA’S PITA 6 pitas for $____ EAT-A PITA 10 pitas for $____ uc e PITA BREAD # of pitas (x) cost (y) 2 $1.00 EAT-A PITA # of pitas (x) cost (y) ot R $5 ep r PAPA’S PITA od 1. Complete the tables and graphs. The graph for EAT-A PITA is provided. A partial table for PAPA’s PITA is provided. Use tables and graphs to complete pricing circles above. Assume proportional relationships. pl e: D o N 2. Which is the better buy? Use entries in the tables or graphs to explain your reasoning. 3. Write equations to relate the number of pitas to cost. y = ______________ EAT-A PITA y = ______________ m PAPA’S PITA Sa 4. How can you determine unit rate from the equation? Linear Functions Unit (Student Packet) $0 1 5 5. Identify the coordinates when x = 1 PAPA’S PITA (1, ____) EAT-A PITA (1, ____) 6. What does this represent in the context of the problem? 7. Identify the coordinates when x = 0 PAPA’S PITA (0, ____) EAT-A PITA (0, ____) What does this represent in the context of the problem? LF3 – SP10 Multiple Representations 3 3.2 Best Buy Problems CROISSANTS CURVEY’S 8 croissants for $____ uc e MOON’S 5 croissants for $____ # of croissants (x) CURVEY’S cost (y) # of croissants (x) cost (y) 4 $2.00 ot R $5 ep r MOON’S od 1. Complete the tables and graphs. The graph for Moon’s Croissants is provided. A partial table for Curvey’s is provided. Use tables and graphs to complete pricing circles above. $0 N 2. Which is the better buy? Use entries in the tables or graphs to explain your reasoning. 1 5 pl e: D o 5. Identify the coordinates when x = 1 3. Write equations to relate the number of croissants to cost. MOON’S y = _____________ CURVEY’S y = _____________ Sa m 4. How can you determine unit rate from the equation? Linear Functions Unit (Student Packet) MOON’S (1, ____) CURVEY’S (1, ____) 6. What does this represent in the context of the problem? 7. Identify the coordinates when x = 0 MOON’S (0, ____) CURVEY’S (0, ____) What does this represent in the context of the problem? LF3 – SP11 Multiple Representations 3 3.3 Rate Graphs RATE GRAPHS Set (Goals) uc e Ready (Summary) ep r Go (Warmup) od • Solve problems involving rates, average speed, distance, and time. • Represent situations graphically and interpret the meaning of specific parts of a graph. We will use words, pictures, tables of numbers, and graphs to represent rates. We will relate the various representations to each other. Chris went jogging at the park. Use the graph to complete the table. Distance ot R 600 yd Number of Minutes pl e: D Time Period o 0 N 200 yd From 0 minutes to 2 minutes 2. From 2 minutes to 4 minutes 3. From 0 minutes to 4 minutes Distance Traveled 4 min Graph is not drawn to scale. Average Rate of Speed m 1. 2 min Time Sa 4. In what part of the jog did Chris run faster, the initial two minutes or the last two minutes? Explain by referencing numbers and the shape of the graph. Linear Functions Unit (Student Packet) LF3 – SP12 Multiple Representations 3 3.3 Rate Graphs POURING WATER 1 uc e Your teacher will give you a small cup and a clear container. Fill up the small cup with water and pour it into the clear container. After each pour, you will measure and record the height of the water in millimeters. 2. Make a graph of the data in your table. o N Height in Millimeters ot R ep r od 1. Make a sketch of the clear container used pl e: D 3. Record your data in the table Number of Pours 1 Height in Millimeters 2 3 m 4 Sa 5 6 7 Linear Functions Unit (Student Packet) 0 Number of Pours LF3 – SP13 Multiple Representations 3 3.3 Rate Graphs POURING WATER 2 2. Container 2 Graph: ______ Graph: ______ Explain: Explain: ot R ep r od 1. Container 1 uc e Suppose you poured water into these containers at a constant rate. • Match each container with an appropriate graph below. • Write one or two sentences to justify each choice. 4. Container 4 Explain: Explain: C. D. Height of Water m Sa Number of Pours Height of Water B. Height of Water A. Graph: ______ Height of Water pl e: D Graph: ______ o N 3. Container 3 Number of Pours Linear Functions Unit (Student Packet) Number of Pours Number of Pours LF3 – SP14 Multiple Representations 3 3.3 Rate Graphs Suppose you poured water into these different containers at a constant rate. • Sketch a graph for each. • Write one or two sentences to justify each sketch. 6. Container 6 Graph: Graph: Height of Water o N Height of Water ot R ep r od 5. Container 5 uc e POURING WATER 2 (Continued) pl e: D Number of Pours Explain: Sa m Explain: Number of Pours Linear Functions Unit (Student Packet) LF3 – SP15 Multiple Representations 3 3.3 Rate Graphs MATCH THE TABLE TO THE GRAPH uc e Without plotting points, match each input-output table with a graph below. Write one or two sentences to justify each choice. Look for constant, increasing, or decreasing rates of change. 2. 1. Input (x) 0 1 2 3 4 5 6 Output (y) 1 4 7 10 13 16 19 od Output (y) 1 3 5 7 9 11 13 ep r Input (x) 0 1 2 3 4 5 6 Graph: ______ Explain: 3. ot R Graph: ______ Explain: 4. o B. Explain: C. y D. y y Sa m y Output (y) 1 7 12 16 19 21 22 Graph: ______ Graph: ______ Explain: A. Input (x) 0 1 2 3 4 5 6 N Output (y) 1 2 4 7 11 16 22 pl e: D Input (x) 0 1 2 3 4 5 6 x Linear Functions Unit (Student Packet) x x x LF3 – SP16 Multiple Representations 3 3.3 Rate Graphs MAKE THE NUMBERS FIT uc e Make up an appropriate table of numbers for each graph. Use estimates only. 1. y x y od 5 x ep r 5 2. x y y 3. y x 60 y 30 4. pl e: D o x N ot R 50 y y 30 Sa m x x 30 Linear Functions Unit (Student Packet) x 30 LF3 – SP17 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review VOCABULARY, SKILL BUILDERS, AND REVIEW Match the words to the clues. Words Clues uc e FOCUS ON VOCABULARY a. This graph is a straight line. It is expressed in the form y = mx + b 1. __________graph of a function b. A rate for one unit of measure. Example: 80 miles per hour ot R 2. __________input-output rule ep r od 1. __________function c. A rule that establishes an output value for each given input value d. A ratio in which the numbers have units attached to them. pl e: D o 3. __________linear function N Example: y = 6x – 2 e. A linear function where one variable is a multiple of another 5. __________unit rate f. m 4. __________rate Sa 6. __________ variables 7. __________direct proportion Linear Functions Unit (Student Packet) In the equation d = rt, the quantities d, r, and t are _________. g. Ordered pairs represented on a coordinate grid h. The set of ordered pairs (x, y) LF3 – SP18 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 1 Compute. -3 + (-5) 3. 4. 8−3 5. 6 + (-6) 6. 7. -3 − (-12) 8. -6 − 8 10. -8 • 2 13. 14 ÷ (-7) ot R 9. 10 -2 o pl e: D 14. -32 -4 9 − (-4) 5 − (-8) 12. -24 6 15. 5 • (-3) N 11. 4−7 uc e 2. od -9 + 2 ep r 1. Solve. 17. If 6 pencils cost $1.38, then what is the cost of 1 pencil? Sa m 16. If 1 pencil costs $0.19, then what is the cost of 5 pencils? Linear Functions Unit (Student Packet) LF3 – SP19 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 2 1. -6 + x < -4 Think (write in words): Think (write in words): Solution: Solution: Graph: Graph: Check a point on the ray. Check a point on the ray. ot R ep r od 2. -x > -5 + 3 uc e Solve each inequality using a mental strategy and graph. Solve each equation using a mental strategy or cups and markers. 3. 10 – b = -3 k−2 -6 = -3 pl e: D o N 4. 6. 30 = -5(m + 2) 7. 2x + 3 = x + 5 8. 3 (x – 4 ) = 12 Sa m 5. -8 = 8 + n Linear Functions Unit (Student Packet) LF3 – SP20 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 3 1. Step 3 Step # 1 2 # of toothpicks 3 5 Step 4 3 4 5 od Step 2 . . . 10 . . . 250 ep r Step 1 uc e For each problem, sketch step 4, complete the table, define your variables, and write an explicit rule for the number of toothpicks based on the step number. ot R Define variables: Rule using symbols: N 2. 1 Step 3 2 pl e: D Step # Step 2 o Step 1 3 Step 4 4 5 . . . 10 . . . 250 # of toothpicks Define variables: m Rule using symbols: Sa Translate each word phrase into symbols. 3. The product of a number and 5, decreased by 7 Linear Functions Unit (Student Packet) 4. The difference between 7 and the product of a number and 5 LF3 – SP21 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 4 od y 1 7 9 5 7 4. (1, -2), (-2, 1), (-1, -2), (2, 1) 6. 2 8 2 8 4 6 4 6 1 3 5 N 1 3 5 9 3. (0, 2), (1, -2), (2, 2), (3, -2) x 3 5 1 3 9 ep r 5. 2. y 1 3 5 7 9 ot R 1. x 1 3 5 7 9 uc e For each of the following tables, sets of ordered pairs, mapping diagrams, or graphs write YES if it could represent a function or NO if it could not. For the NOs, explain why not. 8. pl e: D o 7. 10 Sa m 9. Make up reasonable x-y values for the graph. Could this graph represent a function? Explain. y x y 10 Linear Functions Unit (Student Packet) x LF3 – SP22 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 5 Cost (y) # of pairs (x) cost (y) ot R ep r # of pairs (x) HOSIERY HUT od SOCKS ‘R WE HOSIERY HUT 6 pairs of socks for $7.80 uc e SOCKS ‘R WE 4 pairs of socks for $6.00 1. Fill in the table. Which is the better buy? Use entries in the tables to explain your reasoning. pl e: D o N 2. Label and scale the grid. Graph the data using two different colors. Explain which graph illustrates a slower rise in price. 3. Find the unit rates for pairs of socks at both shops. Use these numbers to explain which has the better buy. m 4. Write equations to relate the number of pairs of socks to cost. y = ______________________ HOSIERY HUT y = ______________________ Sa SOCKS ‘R WE 5. How can you determine unit rate from the equation? Linear Functions Unit (Student Packet) LF3 – SP23 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 6 Match each equation to one set of ordered pairs and also to one graph. Ordered pairs y = 2x 2. y = 2x + 3 3. y = 3x + 2 4. y = 3x – 2 5. y = -x + 3 6. y = -x a. (0, 0) (1, -1) (-1, 1) c. (0, 3) (1, 5) (-1, 1) e. (0, 2) (1, 5) (-1, -1) ot R h. (0, 0) (1, 2) (-1, -2) d. (0, 3) (1, 2) (-1, 4) f. (0, -2) (1, 1) (-1, -5) i. pl e: D o N g. b. ep r od 1. Graph uc e Equation k. l. Sa m j. Linear Functions Unit (Student Packet) LF3 – SP24 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 7 uc e Pat went running at the park. Use the graph to complete the table. od 400 yd 0 1 min 4 min Time Graph is not drawn to scale. Distance traveled Average rate of speed ot R Time period ep r Distance 600 yd From 0 minutes to 1 minute 2. From 1 minute to 4 minutes 3. From 0 minutes to 4 minutes N 1. 5. Suppose you poured water into this container at a constant rate. Sketch a graph and write one or two sentences to justify it. Sa m Explain: Linear Functions Unit (Student Packet) Graph: Height of Water pl e: D o 4. In what part of the jog did Pat run faster, the initial one minute or the last three minutes? Explain by referencing numbers and the shape of the graph. Number of Pours LF3 – SP25 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 8 1. Graph: ______ Explain: y B. Output (y) 19 16 13 10 7 4 1 od Input (x) 0 1 2 3 4 5 6 y C. y ot R A. Output (y) 13 11 9 7 5 3 1 ep r Input (x) 0 1 2 3 4 5 6 2. Graph: ______ Explain: uc e Without plotting the ordered pairs, match each input-output table with a graph below. Write one or two sentences to justify each choice. x x N x Make up an appropriate table of numbers for each graph. Use estimates only. 3. 4. o y x y Sa m x y y pl e: D x Linear Functions Unit (Student Packet) x LF3 – SP26 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review SKILL BUILDER 9 2. B m∠A = 50 , C m∠B = 90 , D od A E m∠C = _____ F m∠D = 120 , m∠E = m∠F , m∠E = ____ ep r 1. uc e Apply each geometry fact to find angles. The sum of the measures of the angles in a triangle = 180o. If two angles are supplementary, then their sum is 180o. 4. p m∠p = 140 , q m∠q = _____ ot R 3. w x m∠w = m∠x m∠w = ______ N 6. Solve the problem. Use guess and check if needed. pl e: D Guess o Two angles are supplementary. One angle is 58o more than the other. Find the larger angle. First angle Make and sketch and Check S = _____? Sum of angles Second angle High? Low? Correct? m x Equation Sa Write an equation and solve it if you can. Linear Functions Unit (Student Packet) and Solution Answer the question. Verify the solution using the equation. LF3 – SP27 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review TEST PREPARATION uc e Show your work on a separate sheet of paper and choose the best answer. 1. Which graph best matches the input-output below? A. y 1 2 B. 2 4 3 6 4 8 5 10 od 0 0 C. y y x x x ot R x D. y ep r Input (x) Output (y) 2. The Office Supply Store and Office Plus both sell notebooks. The Office Supply Store sells 8 notebooks for $7.12. Office Plus sells 5 notebooks for $5.25. Which store offers the better buy? N The Office Supply Store # of 8 16 24 notebooks (x) cost (y) 40 o 32 pl e: D A. Office Plus Office Plus # of notebooks (x) cost (y) 10 20 30 40 50 B. Office Supply C. The prices are the same D. Can’t tell from information given. 3. Which representation below could match the linear function graphed here? m A. The table Sa Input (x) Output (y) B. The ordered pairs 0 0 2 -1 -2 1 -3 2 C. The equation y = -2x + 0 Linear Functions Unit (Student Packet) (-1, 2) (2, -3) (1, -2) (-2, 3) D. The equation y = 2 x 1 LF3 – SP28 Multiple Representations 3 3.4 Vocabulary, Skill Builders, and Review KNOWLEDGE CHECK uc e Show your work on a separate sheet of paper and write your answers on this page. 3.1 Introduction to Functions Which of the following could represent a function? Explain. 2. y = 4x – 5 3. 4. ep r y 1 2 3 4 ot R x 0 1 1 2 od 1. (2, 5) (3, 5) (4, 5) (5, 5) 3.2 Best Buy Problems T-Shirt Mania and Shirts R’ Us sell souvenir t-shirts. T-Shirt Mania charges $18 for three t-shirts and Shirts R’ Us charges $25 for four t-shirts. N 5. Find the unit rates for t-shirts at both stores. Use the numbers to explain which store has the better buy. o 6. Write the equations to relate the number of t-shirts to cost for both stores. pl e: D T-Shirt Mania # of t-shirts (x) 3 6 cost (y) 9 12 Shirts R’ Us # of t-shirts (x) 4 8 12 16 cost (y) 3.3 Rate Graphs m 7. Make an appropriate table of numbers for each graph. Use estimates only. y y 5 Sa x x Linear Functions Unit (Student Packet) 5 LF3 – SP29 Multiple Representations 3 Sa m pl e: D o N ot R ep r od uc e This page is left intentionally blank for notes. Linear Functions Unit (Student Packet) LF3 – SP30 Multiple Representations 3 Sa m pl e: D o N ot R ep r od uc e This page is left intentionally blank for notes. Linear Functions Unit (Student Packet) LF3 – SP31 Multiple Representations 3 Sa m pl e: D o N ot R ep r od uc e This page is left intentionally blank for notes. Linear Functions Unit (Student Packet) LF3 – SP32 Multiple Representations 3 HOME-SCHOOL CONNECTION Here are some questions to review with your young mathematician. 8 16 24 32 40 # of cookies (x) cost (y) 10 20 30 40 50 ep r # of cookies (x) cost (y) Cookieland od Cookies n’ Things uc e 1. Cookies n’ Things charges $3.20 for 8 cookies. Cookieland charges $4.50 for 10 cookies. Which store has the better buy for cookies? x ot R 2. Make an appropriate table of numbers for each graph. Use estimates only. Q y N 5 x 5 m pl e: D o 3. Could the graph from problem 2 represent a function? Explain. Sa Parent (or Guardian) Signature ____________________________ Linear Functions Unit (Student Packet) LF3 – SP33 Multiple Representations 3 COMMON CORE STATE STANDARDS – MATHEMATICS STANDARDS FOR MATHEMATICAL CONTENT 7.RP.2b 7.RP.2c 7.RP.2d 8.EE.5 8.F.1 uc e Compare properties of two functions each represented in a different way (algebraically, graphically, numerically in tables, or by verbal descriptions). For example, given a linear function represented by a table of values and a linear function represented by an algebraic expression, determine which function has the greater rate of change. Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values. Describe qualitatively the functional relationship between two quantities by analyzing a graph (e.g., where the function is increasing or decreasing, linear or nonlinear). Sketch a graph that exhibits the qualitative features of a function that has been described verbally. Create equations in two or more variables to represent relationships between quantities; graph equations on coordinate axes with labels and scales. pl e: D 8.F.4 o N 8.F.2 od 7.RP.1 ep r 6.EE.9 Make tables of equivalent ratios relating quantities with whole-number measurements, find missing values in the tables, and plot the pairs of values on the coordinate plane. Use tables to compare ratios. Use variables to represent two quantities in a real-world problem that change in relationship to one another; write an equation to express one quantity, thought of as the dependent variable, in terms of the other quantity, thought of as the independent variable. Analyze the relationship between the dependent and independent variables using graphs and tables, and relate these to the equation. For example, in a problem involving motion at constant speed, list and graph ordered pairs of distances and times, and write the equation d = 65t to represent the relationship between distance and time. Compute unit rates associated with ratios of fractions, including ratios of lengths, areas and other quantities measured in like or different units. For example, if a person walks 1/2 mile in each 1/4 hour, compute the unit rate as the complex fraction 1/2/1/4 miles per hour, equivalently 2 miles per hour. Identify the constant of proportionality (unit rate) in tables, graphs, equations, diagrams, and verbal descriptions of proportional relationships. Represent proportional relationships by equations. For example, if total cost t is proportional to the number n of items purchased at a constant price p, the relationship between the total cost and the number of items can be expressed as t = pn. Explain what a point (x, y) on the graph of a proportional relationship means in terms of the situation, with special attention to the points (0, 0) and (1, r) where r is the unit rate. Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways. For example, compare a distance-time graph to a distance-time equation to determine which of two moving objects has greater speed. Understand that a function is a rule that assigns to each input exactly one output. The graph of a function is the set of ordered pairs consisting of an input and the corresponding output. ot R 6.RP.3a 8.F.5 A-CED-2 STANDARDS FOR MATHEMATICAL PRACTICE Make sense of problems and persevere in solving them. MP2 Reason abstractly and quantitatively. m MP1 Construct viable arguments and critique the reasoning of others. MP4 Model with mathematics. MP5 Use appropriate tools strategically. MP6 Attend to precision. MP7 Look for and make use of structure. MP8 Look for and express regularity in repeated reasoning. Sa MP3 Linear Functions Unit (Student Packet) LF3 – SP34