2.1 Exercise Set. 190 Chapter 2 Functions, Equations, and Inequalities. Solve.

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1 90 Chapter Functions, Equations, and Inequalities. Exercise Set Solve.. x.. x 0. x 6 0. x 9 6. x x 8. 9 x x x. x 7 x. x x. x x 6. x x 7. x 7x 6. x 9x 7 7. x x x 6 x 8. x 7 x 6x x x 6 x x x. x 7 x 7 9. x x. x x 7. Hbrid Vehicles. Each ear more Americans purchase vehicles with environmentall friendl gasoline-electric hbrid engines. In 00 U.S. hbrid registrations rose to,. This was a.8% increase over the number registered in 00. (Source: R.L. Polk & Co.) How man hbrid vehicles were registered in the U.S. in 00?,7 hbrid vehicles 6 6. Where the Textbook Dollar Goes. Of each dollar spent on textbooks at college bookstores,. cents goes to the college store for profit, store operations, and personnel. On average, a college student spends $0 per ear for textbooks. (Source: National Association of College Stores) How much of this expenditure goes to the college store? About $6. 7. U.S. Album Sales. Sales of 8.0 million music albums were recorded in the U.S. in the first quarter of 00 while.7 million albums were sold in the same period in 00. (Source: Nielsen SoundScan) What was the percent of increase in U.S. album sales from 00 to 00? About 9.% 8. The DVD Boom. The success of the DVD is making a large impact on the movie industr. Americans spent $.8 billion to bu and rent DVDs and videocassettes between Januar and mid- March in 00. This was $.0 billion more than was spent at the box office. (Source: The New York Times,April 0, 00) How much was spent at the box office during this period of time? $.78 billion 9. High-Speed Internet Access. In 00 the number of U.S. households with broadband Internet access

2 Section. Linear Equations, Functions, and Models 9 was projected to be.8 million in 006. This is.6 million more households than in 00. (Source: Forrester Research) How man U.S. households had broadband Internet access in 00? 9. million households 0. Fast-Food Nutrition Information. Together, a Big Mac and an order of Super-Size fries at McDonald s contain 00 calories. The fries contain 0 calories more than the Big Mac. (Source: American Journal of Public Health, Februar 00) How man calories are in each? Big Mac: 90 calories; fries: 60 calories. Nutrition. A slice of carrot cake from the popular restaurant The Cheesecake Factor contains 60 calories. This is three-fourths of the average dail calorie requirement for man adults. (Source: The Center for Science in the Public Interest) Find the average dail calorie requirement for these adults. 080 calories. Television Viewers. Television s most popular series finale of all time, the last episode of M*A*S*H, was seen b twice as man viewers as the series finale of Friends. Together, the two finales had 7. milion viewers. (Source: Nielsen Media Research) How man viewers watched each finale? M*A*S*H : 0 million viewers; Friends :. million viewers. Amount Borrowed. Tamisha borrowed mone from her father at % simple interest to help pa her tuition at Wellington Communit College. At the end of r, she owed a total of $6 in principal and interest. How much did she borrow? $00. Amount of an Investment. Khalid makes an investment at % simple interest. At the end of r, the total value of the investment is $60. How much was originall invested? $00. Sales Commission. Ran, a consumer electronics salesperson, earns a base salar of $00 per month and a commission of 8% on the amount of sales he makes. One month Ran received a $8 pacheck. Find the amount of his sales for the month. $ Commission vs. Salar. Juliet has a choice between receiving an $800 monthl salar from Pearson s Furniture or a base salar of $600 and a % commission on the amount of furniture she sells during the month. For what amount of sales will the two choices be equal? $ Cab Fare. Cit Cabs charges a $.7 pickup fee and $.0 per mile traveled. Diego s fare for a crosstown cab ride is $9.7. How far did he travel in the cab? mi 8. Hourl Wage. Soledad worked 8 hr one week and earned a $ pacheck. She earns time and a half (. times her regular hourl wage) for the hours she works in excess of 0. What is Soledad s regular hourl wage? $ Angle Measure. In triangle ABC,angle B is five times as large as angle A.The measure of angle C is less than that of angle A. Find the measures of the angles. (Hint: The sum of the angle measures is 80.) 6, 0, 0. Angle Measure. In triangle ABC,angle B is twice as large as angle A.Angle C measures 0 more than angle A. Find the measures of the angles. 0, 80, 60. Test Plot Dimensions. Morgan s Seeds has a rectangular test plot with a perimeter of m.

3 9 Chapter Functions, Equations, and Inequalities The length is m more than the width. Find the dimensions of the plot. Length: 9 m; width: 68 m w l. Garden Dimensions. The children at Tin Tots Da Care plant a rectangular vegetable garden with a perimeter of 9 m. The length is twice the width. Find the dimensions of the garden. Length: m; width: 6. m. Soccer Field Dimensions. The width of the soccer field recommended for plaers under the age of is d less than the length. The perimeter of the field is 0 d. (Source: U.S. Youth Soccer) Find the dimensions of the field. Length: 00 d; width: 6 d. Poster Dimensions. Marissa is designing a poster to promote the Talbot Street Art Fair. The width of the poster will be two-thirds of its height and its perimeter will be 00 in. Find the dimensions of the poster. Width: 0 in.; height: 0 in.. Water Weight. Water accounts for 0% of a woman s weight (Source: National Institute for Fitness and Sport). Kimiko weighs lb. How much of her bod weight is water? 67. lb 6. Water Weight. Water accounts for 60% of a man s weight (Source: National Institute for Fitness and Sport). Emilio weighs 86 lb. How much of his bod weight is water?.6 lb 7. Train Speeds. The speed of an Amtrak passenger train is mph faster than the speed of a Central Railwa freight train. The passenger train travels 00 mi in the same time it takes the freight train to travel 0 mi. Find the speed of each train. Freight: 66 mph; passenger: 80 mph 8. Distance Traveled. A private airplane leaves Midwa Airport and flies due east at a speed of 80 km h. Two hours later, a jet leaves Midwa and flies due east at a speed of 900 km h. How far from the airport will the jet overtake the private plane? 0 km 9. Traveling Upstream. A kaak moves at a rate of mph in still water. If the river s current flows at a rate of mph, how long does it take the boat to travel 6 mi upstream?. hr 0. Fling into a Headwind. An airplane that travels 0 mph in still air encounters a 0-mph headwind. How long will it take the plane to travel 00 mi into the wind?. hr. Fling with a Tailwind. An airplane that can travel 7 mph in still air is fling with a -mph tailwind. How long will it take the plane to travel 700 mi with the wind?.7 hr. Traveling Downstream. Angelo s kaak travels km h in still water. If the river s current flows at a rate of km h, how long will it take him to travel 0 km downstream?. hr. Investment Income. Erica invested a total of $000, part at % simple interest and part at % simple interest. At the end of r, the investments had earned $76 interest. How much was invested at each rate? $00 at %; $600 at %. Student Loans. Dimitri s two student loans total $9000. One loan is at % simple interest and the other is at 6% simple interest. At the end of r, Dimitri owes $9 in interest. What is the amount of each loan? $800 at %; $00 at 6%. NCAA Violations. Colleges and universities are responsible for self-reporting their secondar violations to the National Collegiate Athletic Association. (Most secondar violations are honest mistakes for which there is rarel a penalt.) One ear, Division I and Division II schools together reported 989 secondar violations. Division I schools reported about 6. times as man secondar violations as Division II schools. (Source: NCAA) How man secondar violations did each division report? I: about 7 violations; II: about 6 violations

4 Section. Linear Equations, Functions, and Models 9 6. Working Pharmacists. It is estimated that there will be,00 working pharmacists in the United States in 00. This is about.8 times the number of working pharmacists in 97. (Source: U.S. Department of Health and Human Services) Find the number of working pharmacists in the United States in 97. About,0 working pharmacists in Florida than in an other state. A total of,07,866 vanit plates were sold in Florida in a recent ear. These plates accounted for.6% of all plates sold in Florida. (Source: The Fredericksburg, VA Free Lance-Star) How man license plates in all were sold in Florida? About 8,76,79 plates 9. Erosion. Because of erosion, Horseshoe Falls, one of the two falls that make up Niagara Falls, is migrating upstream at a rate of ft per ear (Source: Indianapolis Star, Februar, 999). At this rate, how long will it take the falls to move one-fourth mile? 660 r 7. Instant Messenger Services. AOL s Instant Messenger Service and Microsoft s MSN Messenger Service had a total of 8.9 million users in a recent month. AOL had. million more users than Microsoft. (Source: ComScore Media Matrix) How man users did each service have? AOL:. million users; Microsoft: 9. million users 8. Vanit Plates. More vanit plates (automobile license plates personalized b the owner) are issued 60. Volcanic Activit. A volcano that is currentl about one-half mile below the surface of the Pacific Ocean near the Big Island of Hawaii will eventuall become a new Hawaiian island, Loihi. The volcano will break the surface of the ocean in about 0,000 r. (Source: U.S. Geological Surve) On average, how man inches does the volcano rise in a ear? 0.66 in. per ear Find the zero of the linear function. 6. f x x 6. f x x 0 6. f x x f x 8 x 8 6. f x 6 x f x x f x x 68. f x 8x f x x f x x 7. f x 0 x 0 7. f x x. 7. f x x f x x 9 7. f x x 76. f x x 7

5 9 Chapter Functions, Equations, and Inequalities In Exercises 77 8, use the given graph to find each of the following: (a) the x-intercept and (b) the zero of the function. 77. (a), 0 ; (b) 78. (a), 0 ; (b) 79. x (a), 0 ; (b) 8. (a) x, 0 ; (b) x x 80. (a), 0 ; (b) 8. x x (a), 0 ; (b) Solve. 8. A bh,for b (Area of a triangle) 8. A r,for (Area of a circle) 8. P l w,for w (Perimeter of a rectangle) 86. A P Prt,for r (Simple interest) r A P Pt 87. A h b b,for h (Area of a trapezoid) h A b b 88. A h b b,for b 89. V r,for (Volume of a sphere) r 90. V r,for r 9. F 9 C,for C (Temperature conversion) 9. Ax B C,for (Standard linear equation) 9. Ax B C,for A 9. w h l p,for w 9. w h l p,for h 96. x,for 97. x 6,for 98. T 0 I,000,for I 99. a b bcd,for b 00. q p np,for p b A h b A r r h w V C F 9 P l C Ax B Answers to Exercises 88, 90, and 9 00 can be found on p. IA-.