Authors and Consultants First Nations, Métis
Transcription
Authors and Consultants First Nations, Métis
tio n ic a Authors and Consultants Pu bl Cathy Canavan-McGrath, Hay River, Northwest Territories Serge Desrochers, Calgary, Alberta Hugh MacDonald, Edmonton, Alberta Carolyn Martin, Edmonton, Alberta Michael Pruner, Vancouver, British Columbia Hank Reinbold, St. Albert, Alberta Rupi Samra-Gynane, Vancouver, British Columbia Carol Shaw, Winnipeg, Manitoba Roger Teshima, Calgary, Alberta Darin Trufyn, Edmonton, Alberta First Nations, Métis, and Inuit Cultural Reviewers e- Joanna Landry, Regina, Saskatchewan Darlene Olson-St. Pierre, Edmonton, Alberta Sarah Wade, Arviat, Nunavut Cultural Reviewer Pr Karen Iversen, Edmonton, Alberta Assessment Reviewer Gerry Varty, Wolf Creek, Alberta principles of Mathematics 11 editorial director Linda Allison director, Content and Media production Linh Vu publisher, Mathematics Colin Garnham Managing editors, development Erynn Marcus Alexandra Romic Content production editors Debbie Davies Montgomery Kersell Susan Lee Copyeditor Paula Pettit-Townsend product Manager Linda Krepinsky ISBN-13: 978-0-17-650412-0 ISBN-10: 0-17-650412-5 Printed and bound in Canada 2 3 4 14 13 12 11 Pr e- For more information contact Nelson Education Ltd., 1120 Birchmount Road, Toronto, Ontario M1K 5G4. Or you can visit our Internet site at http://www.nelson.com. Cover image Randy Lincks/Photolibrary Asset Coordinator Suzanne Peden illustrators Nesbitt Graphics, Inc. Compositor Nesbitt Graphics, Inc. production Coordinator Susan Ure photo/permissions researcher David Strand design director Ken Phipps Cover research Debbie Yea Pu Copyright © 2011 by Nelson Education Ltd. Cover design Ken Phipps indexers Marilyn Augst Noeline Bridge bl developmental editors Rachelle Boisjoli Kathryn Chris Shirley Barrett Brenda McLoughlin Bob Templeton, First Folio Resource Group Inc. Jacqueline Williams interior design Nesbitt Graphics, Inc. Peter Papayanakis ic a proofreader Susan McNish program Manager Colin Bisset editorial Assistant Jessica Reeve Authors Cathy Canavan-McGrath Michael Pruner Carol Shaw Darin Trufyn Hank Reinbold tio n lead educator Chris Kirkpatrick All rights reserved. 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Reviewers and Advisory Panel Karen Buro Instructor, Department of Mathematics and Statistics MacEwan University Edmonton, AB Sean Chorney Mathematics Department Head Magee Secondary School School District 39 Vancouver, BC Carolyn Martin Department Head of Mathematics Archbishop MacDonald High School Edmonton Catholic School Board Edmonton, AB tio n Hank Reinbold Retired Educator Morinville, AB Rupi Samra-Gynane Vice-Principal Magee Secondary School Vancouver School Board (#39) Vancouver, BC Steven Erickson Mathematics Teacher Sisler High School Winnipeg School Division Winnipeg, MB Carol Shaw Mathematics Department Head Elmwood High School Winnipeg School Division Winnipeg, MB ic a Serge Desrochers Bishop McNally High School Calgary Catholic School District Calgary, AB Roger Teshima Learning Leader of Mathematics Bowness High School Calgary Board of Education Calgary, AB George Lin Mathematics Department Head Pinetree Secondary School School District 43 Coquitlam, BC Sarah Wade Curriculum Developer Nunavut Board of Education Ottawa, ON Pu bl Joanna Landry Coordinator, First Nations, Inuit, and Métis Education Services Regina Catholic Schools (#81) Regina, SK Pr e- Hugh MacDonald Principal Austin O’Brien Catholic High School Edmonton Catholic School District Edmonton, AB NEL Reviewers and Advisory Panel iii table of Contents Features of Nelson Principles of Mathematics 11 viii 2 Getting Started: The Mystery of the Mary Celeste 4 1.1 Making Conjectures: Inductive Reasoning Math in Action: Oops! What Happened? 1.2 Exploring the Validity of Conjectures 1.3 Using Reasoning to Find a Counterexample to a Conjecture 6 15 Chapter 2: Properties of Angles and Triangles 66 Getting Started: Geometric Art 68 2.1 Exploring Parallel Lines 70 2.2 Angles Formed by Parallel Lines 73 tio n Chapter 1: Inductive and Deductive Reasoning Applying Problem-Solving Strategies: Checkerboard Quadrilaterals 16 83 Mid-Chapter Review 84 2.3 Angle Properties in Triangles 86 2.4 Angle Properties in Polygons Applying Problem-Solving Strategies: Analyzing a Number Puzzle 26 Math in Action: “Circular” Homes 94 100 1.4 Proving Conjectures: Deductive Reasoning 27 Mid-Chapter Review 34 History Connection: Buckyballs— Polygons in 3-D 103 1.5 Proofs That Are Not Valid 36 Chapter Self-Test Chapter Review 104 45 2.6 Proving Congruent Triangles 107 52 Chapter Self-Test 116 58 Chapter Review 117 Pu 1.7 Analyzing Puzzles and Games 2.5 Exploring Congruent Triangles bl 1.6 Reasoning to Solve Problems ic a History Connection: Reasoning in Science 18 24 59 63 Project Connection: Creating an Action Plan 64 121 Project Connection: Selecting Your Research Topic 122 Chapters 1–2 Cumulative Review 124 Pr e- Chapter Task: How Many Sisters and Brothers? Chapter Task: Designing Logos iv Table of Contents NEL 126 Getting Started: Lacrosse Trigonometry 128 3.1 Exploring Side–Angle Relationships in Acute Triangles 130 3.2 Proving and Applying the Sine Law 132 Mid-Chapter Review 142 3.3 Proving and Applying the Cosine Law 144 Math in Action: How Good Is Your Peripheral Vision? History Connection: Fire Towers and Lookouts Applying Problem-Solving Strategies: Analyzing a Trigonometry Puzzle 154 172 Getting Started: Photography 174 4.1 Mixed and Entire Radicals 176 4.2 Adding and Subtracting Radicals History Connection: It’s Radical 4.3 Multiplying and Dividing Radicals Applying Problem-Solving Strategies: Defining a Fractal 163 164 184 190 191 201 Mid-Chapter Review 202 4.4 Simplifying Algebraic Expressions Involving Radicals 204 4.5 Exploring Radical Equations 214 ic a 3.4 Solving Problems Using Acute Triangles Chapter 4: Radicals tio n Chapter 3: Acute Triangle Trigonometry 4.6 Solving Radical Equations 216 Math in Action: How Far Is the Horizon? 224 Chapter Self-Test 225 166 Chapter Review 226 167 Chapter Task: Acute Triangles in First Nations and Métis Cultures Chapter Task: Designing a Radical Math Game 229 169 Project Connection: Creating Your Research Question or Statement Project Connection: Carrying Out Your Research 230 170 Chapter Self-Test Pr e- Pu Chapter Review bl 165 NEL Table of Contents v 234 Chapter 6: Quadratic Functions 318 Getting Started: Comparing Salaries 236 Getting Started: String Art 320 5.1 Exploring Data 238 6.1 Exploring Quadratic Relations 322 6.2 Properties of Graphs of Quadratic Functions 325 5.2 Frequency Tables, Histograms, and Frequency Polygons 241 253 History Connection: Duff’s Ditch tio n Chapter 5: Statistical Reasoning 6.3 Factored Form of a Quadratic Function 337 347 5.3 Standard Deviation 254 Mid-Chapter Review 266 Mid-Chapter Review 351 5.4 The Normal Distribution 269 6.4 Vertex Form of a Quadratic Function 354 282 6.5 Solving Problems Using Quadratic Function Models Applying Problem-Solving Strategies: Predicting Possible Pathways Math in Action: Paper Parabolas 283 History Connection: Trap Shooting 5.6 Confidence Intervals 295 Applying Problem-Solving Strategies: Curious Counting Puzzles 382 ic a 5.5 Z-Scores 368 381 Math in Action: Finding and Interpreting 304 Data in the Media 305 Chapter Review Chapter Task: True-False Tests 383 Chapter Review 384 bl Chapter Self-Test Chapter Self-Test 306 Chapter Task: Parabolas in Inuit Culture 389 311 Project Connection: Identifying Controversial Issues 390 Pu Project Connection: Analyzing Your Data 312 315 Pr e- Chapters 3–5 Cumulative Review vi Table of Contents NEL Chapter 7: Quadratic Equations 392 Chapter 8: Proportional Reasoning 440 Getting Started: Factoring Design 394 Getting Started: Interpreting the Cold Lake Region 442 396 7.2 Solving Quadratic Equations by Factoring 405 7.3 Solving Quadratic Equations Using the Quadratic Formula History Connection: The Golden Ratio 414 422 423 7.4 Solving Problems Using Quadratic Equations 425 Applying Problem-Solving Strategies: Determining Quadratic Patterns Chapter Self-Test 432 433 Chapter Review 434 8.2 Solving Problems That Involve Rates 454 Applying Problem-Solving Strategies: Analyzing a Rate Puzzle 437 438 Pr e- Pu Project Connection: The Final Product and Presentation NEL 462 Mid-Chapter Review 463 8.3 Scale Diagrams 466 8.4 Scale Factors and Areas of 2-D Shapes 475 8.5 Similar Objects: Scale Models and Scale Diagrams 483 8.6 Scale Factors and 3-D Objects 494 Math in Action: Are Prices of TVs Scaled Appropriately? 503 Chapter Self-Test 504 Chapter Review 505 Chapter Task: Mice To Be Here 509 Project Connection: Peer Critiquing of Research Projects 510 Chapters 6–8 Cumulative Review 512 Glossary 514 Answers 519 Index 575 Z-Score Table 580 Credits 582 bl Chapter Task: A Teaching Tool History Connection: Ivy Granstrom 444 453 ic a Mid-Chapter Review 8.1 Comparing and Interpreting Rates tio n 7.1 Solving Quadratic Equations by Graphing Table of Contents vii Features of Nelson Principles of Mathematics 11 Lessons Chapters begin with two-page activities designed to activate concepts and skills you have already learned that will be useful in the coming chapter. Some lessons help to develop your understanding of mathematics through examples and questions. Most lessons give you a chance to explore or investigate a problem. Many of the problems are in a real-life context. 3 tio n Getting Started Getting Started 2.1 Lacrosse Trigonometry Daniel is about to take a shot at a field lacrosse net. He estimates his current position, as shown below. YOU WILL NEED • calculator YOU WILL NEED • dynamic geometry software GOAL Identify relationships among the measures of angles formed by intersecting lines. ic a OR ruler and protractor Exploring Parallel Lines EXPLORE the Math A sports equipment manufacturer builds portable basketball systems, like those shown here. These systems can be adjusted to different heights. goal 6' 65° transversal bl Daniel ? How can you use these estimates to determine the width of the net? A. Does Daniel’s position form a right triangle with the goalposts? B. A primary trigonometric ratio cannot be used to determine the width of the net directly. Explain why. C. Copy the triangle that includes Daniel’s position in the diagram above. Add a line segment so that you can determine a height of the triangle using trigonometry. D. Determine the height of the triangle using a primary trigonometric ratio. E. Create a plan that will allow you to determine the width of the lacrosse net using the two right triangles you created. F. Carry out your plan to determine the width of the net. Chapter 3 Acute Triangle Trigonometry transversal A line that intersects two or more other lines at distinct points. transversal Pr When a transversal intersects two parallel lines, how are the angle measures related? Reflecting a Use the relationships you observed to predict the measures of as many of the angles a to g in this diagram as you can. Explain each of your predictions. 140° b c d f 70 Chapter 2 Properties of Angles and Triangles This team from Caughnawaga toured England in 1867, demonstrating the game. As a result of the tour, lacrosse clubs were established in England. The game then spread around the world. The Canadian team won the bronze medal at the 2009 Women‘s Lacrosse World Cup in Prague, Czech Republic. e g NEL Reflecting These questions give you a chance to reflect on the lesson so far and to summarize what you have learned. WHAT DO You Think? Decide whether you agree or disagree with each statement. Explain your decision. 1. When using proportional reasoning, if you apply the same operation, using the same number, to all the terms, the ratios remain equivalent. 2. If you know the measures of two angles and the length of any side in an acute triangle, you can determine all the other measurements. NEL viii ? When a system is adjusted, the backboard stays perpendicular to the ground and parallel to the supporting post. NEL What Do You Think? Statements about mathematical concepts are presented and you must decide whether you agree or disagree. Use your existing knowledge and speculations to justify your decisions. At the end of the chapter, revisit these statements to decide whether you still agree or disagree. When the adjusting arm is moved, the measures of the angles formed with the backboard and the supporting post change. The adjusting arm forms a transversal . A. e- 128 5' Pu Field lacrosse, Canada‘s national sport, originated with First Nations peoples, probably in central North America. Hundreds of years ago, both the number of players and the size of the field were much greater than in the modern game. The Iroquois peoples of what is now southern Ontario and western New York may have been the first to limit the number of players to 12 or 15. Features of Nelson Principles of Mathematics 11 Getting Started 129 NEL Explore You Will Need Try these at the beginning of each lesson. They may help you think in ways that will be useful in the lesson. YOU WILL NEED t calculator t graph paper t ruler EXPLORE… t World-class sprinters can run 100 m in about 9.8 s. If they could run at this rate for a longer period of time, estimate how far they could run in a minute, in an hour, and in a day. Communication Tip The time 01:20:34.7, or 80:34.7, can also be written as 1 h 20 min 34.7 s or as 80 min 34.7 s. Comparing and Interpreting Rates GOAL Represent, interpret, and compare rates. APPLY the Math INVESTIGATE the Math A triathlon consists of three different races: a 1.5 km swim, a 40 km bike ride, and a 10 km run. The time it takes to “transition” from one race to the next is given as “Trans” in the official records. The setup for the transition area is different in different triathlons. EXAMPLE Simon Whitfield of Victoria, British Columbia, participated in the triathlon in both the 2000 and 2008 Olympic Games. His results for both Olympics are shown below. Cycling Rank Athlete Country Time Trans Time Trans 1 Whitfield Canada 17:56 0:21 58:54 0:17 Cycling Time Total Time 30:52 1:48:24.02 Running Rank Athlete Country Time Trans Time Trans A comparison of two amounts that are measured in different units; for example, keying 240 words/8 min Communication Tip The word “per” means “to each” or “for each.” It is written in units using a slash (/). 30:48 Total Time 1:48:58.47 How can you compare Simon’s speeds in his two Olympic medal-winning triathlons? A. Compare Simon’s times for each race segment in the two triathlons, ignoring the transition times. Which race segment had the greatest difference in Simon’s times? B. Speed, the ratio of distance to time, is an example of a rate . Create a distance versus time graph to compare Simon’s swimming speeds in these triathlons. Express time in hours and distance in kilometres. C. A polygon in which each interior angle measures less than 180°. Viktor’s Solution Zfem\o efe$Zfem\o ZfeZXm\ Determine the slope of each line segment on your distance versus time graph. What do these slopes represent? E. Do the slopes you determined in part D support Carmen’s claim? Explain. Chapter 8 Proportional Reasoning :- :) 8 :( :. The sum of the measures of the angles in n triangles is n(180°). :+ :* :, :- :) 8 :. :( :e :/ I drew an n-sided polygon. I represented the nth side using a broken line. I selected a point in the interior of the polygon and then drew line segments from this point to each vertex of the polygon. The polygon is now separated into n triangles. The sum of the measures of the angles in each triangle is 180°. :/ :e Carmen claims that Simon swam faster in the 2000 Sydney Olympic Games Triathlon than in Beijing in 2008. Explain how the data in the table and in the graph you created in part B support her claim. D. :, Two angles in each triangle combine with angles in the adjacent triangles to form two interior angles of the polygon. Each triangle also has an angle at vertex A. The sum of the measures of the angles at A is 360° because these angles make up a complete rotation. These angles do not contribute to the sum of the interior angles of the polygon. The sum of the measures of the interior angles of the polygon, S(n), where n is the number of sides of the polygon, can be expressed as: S n 180°n 360° S n 180° n 2 The sum of the measures of the interior angles of a convex polygon can be expressed as 180° n 2 . NEL Your Turn 0- Explain why Viktor’s solution cannot be used to show whether the expression 180° n 2 applies to non-convex polygons. Chapter 2 Properties of Angles and Triangles NEL e- +++ 18:18 0:27 58:56 0:29 Time Pu rate Whitfield Canada convex polygon bl 2 ? Reasoning about the sum of the interior angles of a polygon :* Running 2008 Beijing Olympic Games Triathlon: Men Swimming 1 Prove that the sum of the measures of the interior angles of any n-sided convex polygon can be expressed as 180° n 2 . :+ 2000 Sydney Olympic Games Triathlon: Men Swimming New terms and ideas are highlighted in the text. In the margin nearby, you’ll find a definition. ic a 8.1 Definitions tio n Items you will need to carry out the lesson, such as a calculator or graph paper, will be listed here. Communication Tips Pr These tips give explanations for why or when a specific mathematical convention or notation is used. NEL Your Turn These questions appear after each Example. They may require you to think about the strategy presented in the example, or to solve a similar problem. Examples A complete solution to the example problem is given on the left. Explanations for steps in the solution are included in green boxes on the right. Use the examples to develop your understanding, and for reference while practising. Features of Nelson Principles of Mathematics 11 ix Practising The In Summary box presents the Key Ideas for the lesson, and summarizes other useful information under Need to Know. These problems and questions give you a chance to practise what you have just learned. There are a variety of types of questions, from simple practice questions that emphasize skill and knowledge development to problems that require you to make connections, visualize, and reason. In Summary Key Idea t *OEVDUJWFSFBTPOJOHJOWPMWFTMPPLJOHBUTQFDJGJDFYBNQMFT#ZPCTFSWJOH QBUUFSOTBOEJEFOUJGZJOHQSPQFSUJFTJOUIFTFFYBNQMFTZPVNBZCFBCMF UPNBLFBHFOFSBMDPODMVTJPOXIJDIZPVDBOTUBUFBTBDPOKFDUVSF Need to Know t "DPOKFDUVSFJTCBTFEPOFWJEFODFZPVIBWFHBUIFSFE t .PSFTVQQPSUGPSBDPOKFDUVSFTUSFOHUIFOTUIFDPOKFDUVSFCVUEPFTOPU QSPWFJU Closing 15. Create a real-life problem that can be modelled by an acute triangle. Exchange the problem you created with a classmate. Sketch the situation in your classmate’s problem, and explain what must be done to solve it. CHECK Your Understanding Extending 1. Troy works at a ski shop in Whistler, British Columbia, where three ))(%)d Egypt has a square base with sides that are 232.6 m long. The : ; distance from the top of the > = pyramid to each corner of the 8 9 )*)%-d base was originally 221.2 m. a) Determine the apex angle of a face of the pyramid (for example, AEB to the nearest degree. b) Determine the angle that each face makes with the base (for example, EGF to the nearest degree. 2. Tomas gathered the following evidence and noticed a pattern. 23 11 253 17 11 187 62 11 682 41 11 451 Tomas made this conjecture: When you multiply a two-digit number by 11, the first and last digits of the product are the digits of the original number. Is Tomas’s conjecture reasonable? Develop evidence to test his conjecture and determine whether it is reasonable. ic a 17. Cut out two paper strips, each 5 cm wide. Lay them across each other as shown at the right. Determine the area of the overlapping region. Round your answer to the nearest tenth of a square centimetre. PRACTISING 3. Make a conjecture about the sum of two even integers. Develop evidence to test your conjecture. *' History Connection 4. Make a conjecture about the meaning of the symbols and colours in Fire Towers and Lookouts the Fransaskois flag, at the left. Consider French-Canadian history and the province of Saskatchewan. 5. Marie studied the sum of the angles in quadrilaterals and made a conjecture. What conjecture could she have made? Closing 19. Lou says that conjectures are like inferences in literature and hypotheses in science. Sasha says that conjectures are related only to reasoning. With a partner, discuss these two opinions. Explain NEL how both may be valid. Chapter 1 Inductive and Deductive Reasoning Extending For about 100 years, observers have been watching for forest fires. Perched in lookouts on high ground or on tall towers (there are three fire towers in Alberta that are 120 m high), the observers watch for smoke in the surrounding forest. When the observers see signs of a fire, they report the sighting to the Fire Centre. The first observers may have had as little as a map, binoculars, and a horse to ride to the nearest station to make a report. Today, observers have instruments called alidades and report using radios. Alidades consist of a local map, fixed in place, with the tower or lookout at the centre of the map. Compass directions are marked in degrees around the edge of the map. A range finder rotates on an arc above the map. The observer rotates the range finder to get the smoke in both sights, notes the direction, and reports it to the Fire Centre. A computer at the Fire Centre can use the locations of the fire towers and directions from two or more observers to fix the location of the fire. The latitude and longitude are then entered into a helicopter’s flight GPS system. The helicopter’s crew flies to the fire, records a more accurate location, and reports on the fire. bl () < 16. The Great Pyramid at Giza in types of downhill skis are available: parabolic, twin tip, and powder. The manager of the store has ordered 100 pairs of each type, in various lengths, for the upcoming ski season. What conjecture did the manager make? Explain. $BOBEBTNPTUQPQVMBS TLJEFTUJOBUJPOJT8IJTUMFS #MBDLDPNCJO#SJUJTI$PMVNCJB 5IJTBSFBESBXTNPSFUIBO NJMMJPOWJTJUPSTFBDIZFBS tio n In Summary A. B. 20. Photographs lead to conjectures about what was happening around the time that the images were captured. With a partner, develop at least three different conjectures about what could have led to the situation in this photograph. Analyzing a Number Puzzle Arithmagons are number puzzles that have addition as the central operation. They are based on polygons, with a circle at each vertex and a box on each side. The Puzzle The number in each box of an arithmagon is the sum of the two numbers in the circles adjacent to the box. ( ) Chapter 3 Acute Triangle Trigonometry NEL A. dentists recommend it.” Discuss this statement with a partner, and decide whether it is a conjecture. Justify your decision. 22. From a news source, retrieve evidence about an athlete’s current Pu B. Oops! What Happened? estop sign Pr NEL 1.1 Making Conjectures: Inductive Reasoning () (, c) */ +/ -/ Create your own arithmagon. Exchange arithmagons with a partner, and solve your partner’s arithmagon. C. D. E. F. )- What patterns did you notice? What relationship exists between the numbers in the circles and the numbers in the opposite boxes? Describe the strategy you used to solve your partner’s arithmagon. Of the arithmagons you’ve encountered, which was easiest to solve? Explain. Chapter 1 Inductive and Deductive Reasoning NEL (, Math in Action History Connection These tasks give you a chance to apply the math concepts you have learned in a realworld context. Find out how mathematics has been used throughout history, and think about some implications. x 0 The Strategy Investigator: ent: 14:15 -Time of accidcovered Driver of yellow car: -Roads snow nt and -Came to full stop, -Stop sign evide clear of snow s evidentt checked for cars, and -No brake markbecause proceeded through the for either car in r c i n intersection of snow cover Passenger Driver of blue car: r r: -DidnÕt see of blue car: -Driving 60 km/h looking at anything, was the map (speed limit) ap -Had lights on -Saw yellow car Witness at stop sign: but didnÕt stop -Was waiting to cross road -Yellow car didnÕt completely stop before starting to go through the intersection -Blue car driver was speeding (/ (0 Math in Action * , Solve the three triangular arithmagons below. a) b) (. performance or a team’s current performance. Study the evidence, and make a conjecture about the athlete’s or team’s performance over the next month. Justify your conjecture, and discuss the complexity of conjectures about sports. t *EFOUJGZUIFQJFDFTPGHJWFOFWJEFODFUIBUBSFDPOKFDUVSFT t .BLFBDPOKFDUVSFBCPVUXIBUDBVTFEUIFBDDJEFOU t 8IBUFWJEFODFTVQQPSUTZPVSDPOKFDUVSF t *GZPVDPVMEBTLUISFFRVFTUJPOTPGUIFESJWFST PSUIFXJUOFTTXIBUXPVMEUIFZCF t $BOUIFDBVTFPGBOBDDJEFOUTVDIBTUIJT CFQSPWFE 8IZPSXIZOPU + * How could a Fire Centre use trigonometry to determine the location of a fire? How could an observer use trigonometry to estimate the size of a fire? (-+ 21. In advertising, we often see statements such as “four out of five Applying Problem-Solving Strategies Features of Nelson Principles of Mathematics 11 Applying ProblemSolving Strategies These games or puzzles develop your problemsolving skills by allowing you to create and analyze strategies. NEL Mid-Chapter Review Chapter Self-Test Chapter Task See the Mid-Chapter Review for Frequently Asked Questions. Try the suggested Practising questions if you feel you need to test your understanding. Try the Self-Test at the end of the chapter to discover if you have met the learning goals of the chapter. If you are uncertain about how to address any of the questions, look to the FAQs in the Mid-Chapter and Chapter Reviews for support. Have you developed a deep understanding of the mathematics presented in the chapter? Find out by trying this performance task. 1 Mid-Chapter Review Chapter Self-Test Frequently Asked Questions Q: What are the relationships among the angles formed when a transversal intersects two parallel lines? A: When two lines are parallel, the following angle relationships hold: Questions 1 to 5. b a a b Corresponding angles are equal. Study Aid • See Lesson 2.2, Example 2. • Try Mid-Chapter Review Question 6. Study Aid • See Lesson 2.2, Example 3. • Try Mid-Chapter Review Questions 6 and 8. Q: A: e c Alternate interior angles are equal. 2. Frank tosses a coin five times, and each time it comes up tails. He Figure 2 makes the following conjecture: The coin will come up tails on every toss. Is his conjecture reasonable? Explain. e Alternate exterior angles are equal. 3. Koby claims that the perimeter of a pentagon with natural Interior angles on the same side of the transversal are supplementary. number dimensions will always be an odd number. Search for a counterexample to his claim. Draw a diagram that shows parallel lines and a transversal. Label your diagram with any information you know about the lines and angles. State what you know and what you are trying to prove. Make a plan. Use other conjectures that have already been proven to complete each step of your proof. Q: How can you use angles to prove that two lines are parallel? A: Draw a transversal that intersects the two lines, if the diagram does not include a transversal. Then measure, or determine the measure of, a pair of angles formed by the transversal and the two lines. If corresponding angles, alternate interior angles, or alternate exterior angles are equal, or if interior angles on P B the same side of the transversal are supplementary, the lines are parallel. cream. Determine the order in which they are lined up, using these clues: • CandiceisbetweenAndyandBonnie. • DarleneisnexttoAndy. • Bonnieisnotfirst. Explain. Let a 5 9.9. 10a 5 99.9 10a 2 a 5 90 9a 5 90 a 5 10 Q 3 Chapter 2 Properties of Angles and Triangles ? Multiply by 10. Subtract a. Divide by 9. NEL Chapter Review58 8 Chapter 1 Inductive and Deductive Reasoning NEL FREQUENTLY ASKED Questions Q: To use the cosine law, what do you need to know about a triangle? A: You need to know two sides and the contained angle, or three sides in the triangle. For example, you can use the cosine law to determine the length of p. P R 8 cm 72° 6 cm to 3. • Try Chapter Review Questions 6 to 9. You know: • the lengths of two sides. • the measure of the contained angle. You can use the cosine law to determine the length of the side opposite the contained angle, p. p2 5 82 1 62 2 2 182 162 cos 72° Solving for p will determine the length. Pu p Study Aid • See Lesson 3.3, Examples 1 Q What are the measures of all the sides and angles in each triangle in the frame of a tipi? A. Design a tipi. Choose the number of poles, the interior height, and the diameter of the base. B. What regular polygon forms the base of your tipi? What type of triangle is formed by the ground and supporting poles? Explain how you know. Simplify. WHAT DO You Think Now? Revisit What Do You Think? on page 5. How have your answers and explanations changed? S C The frame of a tipi consists of wooden poles supported by an inner tripod. Additional poles are laid in and tied with rope. When the frame is complete, the covering is drawn over the frame using two additional poles. The interior of the tipi creates a roughly conical shape. The number of poles used is indicative of geographic area and people, ranging from 13 to 21 poles. 7. The following proof seems to show that 10 5 9.9. Is this proof valid? D 60° Structures made from acute triangles are used in most cultures. The First Nations and Métis peoples who lived on the Prairies used acute-triangle structures to cook, dry meat, and transport goods and people. Acute triangles are also the support for tipis. Tipis suit a life based on the migration of the buffalo, because they are easily assembled and taken down. Tipis are still used for shelter on camping trips and for ceremonial purposes. Choose a natural number. Double it. Add 20. Divide by 2. Subtract the original number. 6. Andy, Bonnie, Candice, and Darlene are standing in line to buy ice R 60° A Measure alternate interior angles /ARQ and /PSD. If these angles are equal, then AB i CD. 5. Prove that the following number trick always results in 10: Figure 3 Blackfoot tipis Inside a Dakota tipi 4. Prove that the product of two consecutive odd integers is always odd. How can you prove that a conjecture involving parallel lines is valid? For example, determine if AB is parallel to CD. First draw transversal PQ. 84 d 180° � d c a) What would the 4th and 5th structures look like? How many cubes would Danielle need to build each of these structures? b) Make a conjecture about the relationship between the nth structure and the number of cubes needed to build it. c) How many cubes would be needed to build the 25th structure? Explain how you know. Figure 1 Chapter Task Acute Triangles in First Nations and Métis Cultures ic a Lesson 2.2, Example 1. • Try Mid-Chapter Review 3 bl Study Aid • See Lesson 2.1 and 1. Danielle made the cube structures to the left. tio n 2 C. Determine the side lengths of the frame triangles. D. Determine the interior angles of the frame triangles. E. Explain why your design is functional. Project Connection frame triangle Task Checklist ✔ Did you draw labelled diagrams for the problem? ✔ Did you show your work? ✔ Did you provide appropriate reasoning? ✔ Did you explain your thinking clearly? Chapter Task NEL 169 Peer Critiquing of Research Projects Now that you have completed your research for your question/topic, prepared your report and presentation, and assessed your own work, you are ready to see and hear the research projects developed by your classmates. You will not be a passive observer, however. You will have an important role—to provide constructive feedback to your peers about their projects and their presentations. Critiquing a project does not involve commenting on what might have been or should have been. It involves reacting to what you see and hear. For example, pay attention to • strengthsandweaknessesofthepresentation. • problemsorconcernswiththepresentation. Think of suggestions you could make to help your classmate improve future presentations. You can also use the cosine law to determine the measure of /Y . X 2 cm Z 4 cm 5 cm Y You know: • the lengths of all three sides. You can use the cosine law to determine the measure of /Y . 22 5 42 1 52 2 2 142 152 cos Y 2 2 2 42 2 52 5 cos Y 22 142 152 Solving for Y will determine the measure of /Y . When solving a problem that can be modelled by an acute triangle, how do you decide whether to use the primary trigonometric ratios, the sine law, or the cosine law? A: Draw a clearly labelled diagram of the situation to record what you know. • You may be able to use a primary trigonometric ratio if the diagram involves a right triangle. • Use the sine law if you know two sides and one opposite angle, or two angles and one opposite side. • Use the cosine law if you know all three sides, or two sides and the angle between them. e- Q: Study Aid • See Lesson 3.4, Examples 1 to 3. • Try Chapter Review Questions 10 to 12. While observing each presentation, consider the content, the organization, and the delivery. Take notes during the presentation, using the following rating scales as a guide. You can also use these scales to evaluate the presentation. You may need to use more than one strategy to solve some problems. Pr NEL NEL Chapter Review 167 510 Chapter 8 Proportional Reasoning NEL Chapter Review Project Connection Like the FAQ in the Mid-Chapter Review, the FAQ covers the immediately preceding lessons. Practising covers the whole chapter. There are also three Cumulative Reviews (not shown), which you can use to practise skills and use concepts you’ve learned in the preceding chapters. You will be working on a project throughout the year. Project Connections support you as you decide on a topic, do your research, and develop your presentation. Features of Nelson Principles of Mathematics 11 xi