Rate of Change and Slope ALGEBRA 1 LESSON 6-1 10. 2 11. 2 12. 13. – 14. –1 15. –1 16. 17. 18. – 19. – 20. 21. –5 22. 0 23. undefined 24. 0 25. undefined 26. 0 27. in./month 28. $5/person 29. 30 mi/hr 30. 1 2 pages 286–289  Exercises 1. 3; the temperature increases 3°F each hour. 2. 3.95; the cost per person is $3.95. 3. – gal/mi 4. ; there are 2 lb of carbon emissions for 3 h of television use. 5. –16 ; the skydiver descends 16 ft/s. 6. ; the cost of oregano is $1 for 4 ounces. 7. 8. –3 9. 3 4 1 15 3 2 2 3 2 3 2 3 1 4 5 9 9 10 1 2 5 3 6 5 2 3 1 2 2 5 6-1

Rate of Change and Slope ALGEBRA 1 LESSON 6-1 31. 32. 33. –20 34. undefined 35. –3 36. 37. 1 6 38. 39. 40. a. C b. C greatest; A least; the slope 41. a. b. c. Answers may vary. Sample: = 42. 2 ; 3 43. No; for example the line passing through the points such as (1, 6) and (2, 5) has a slope of –1. 44. PQ: ; QR: 0; RS: 5; SP: –1 45. JK: – ; KL: 2; ML: – ;MJ: 2 2 3 1 4 2 3 y2 – y1 x2 – x1 y1 – y2 x2 – x1 2 5 3 5 1 2 1 2 6-1

Rate of Change and Slope ALGEBRA 1 LESSON 6-1 46. a. b. c. d. equal 47. a. Answers may vary. Sample: (0, 0), (1, ) b. Answers may vary. Sample: (0, 0), (1, – ) 48. 0 49. –6 50. 6 51. 4 52. 12 53. 3 54–60. Counter examples may vary. 54. False; it can be neg. or undefined. 55. true 56. False; y = x + 2 57. true 58. False; y = x 59. False; y = 0x 60. true 61. a.111; $111/h b. 52 customers per h 3 4 2 1 6-1

Rate of Change and Slope ALGEBRA 1 LESSON 6-1 62. Friend found instead of . 63. 0 64. – 65. 66. Yes; AB and BC have the same slope. 67. Yes; GH and HI have 68. No; DE and EF do not have the same slope. 69. No; PQ and QR do not have the same slope. 70. Yes; GH and HI have the same slope. 71. No; ST and TU do not 72. C 73. G 74. [2] = ; the slope is . = 12.5%; the grade is 12.5%. [1] finds grade only 75. A 76. c = 3.5n 77. p = 4.95q – 232 78. 0 79. 80. 81. 1 82. –3 83. –4 84. 85. 7 86. 5 87. –10 run rise rise run 1 2 n 2m 1 3 2d – b c – 2a 3 24 1 8 1 8 19 9 1 8 6-1