r • Review Exercises In Exercises 1—6, match the equation with the correct graph. [The graphs are labeled (a), (b), (c), (d), (e), and (f).j (a) 4 112 82 In Exercises 17—20, sketch the graph of the parabola Use a graphing utility to verify your graph. 0 2 18. 8y+x 20.y_8x2=0 y 0 2 17.4x— = 19.l,v2+18x=0 In Exercises 2 1—24, write the equation of the specifie ellipse with center at the origin. 21. Vertices: (±5, 0); Foci: (±4, 0) 22. Vertices: (0, ±10); Foci: (0,±8) 23. Vertices: (0, ±6); Passes through: (2, 2) 24. Vertices: (±7, 0); Passes through: (0, ±6) (c) In Exercises 25—28, sketch the graph of the ellips Use a graphing utility to verify your graph. 2 2 + v 25. 4x (e) 26. 16 2 + 6v 2 = 18 x 8y 48 28.3 + 2 = 6 +4v 2 6x 27. 3 In Exercises 29—32, write the equation of the specifie hyperbola with center at the origin. 2 +2 1. 4x y 2 + 4 3. x 2 y 5. 4x 2 — 2 y = 4 2. 2 y = —4x 4 2 + )12 = 49 4 6. y 2 4 = — y=-2x :‘ + — 144 = 1 12. + = I = - = 13. Vertex: (0, 0); Vertical axis Passes through: (1, 2) 14. Vertex: (0, 0); Passes through: (4, —2) L 15. Vertex: (0, 0); Focus: (—6, 0) 16. Vertex: (0, 0); Focus: (0, 3) 6 16 In Exercises 13—16, write the equation of the specified parabola. Vertical axis I (—1, 0)’’(1 0) 2 + v 8. 16x 2 0 7. x 2 + 2Oy 49 yJ 4 2 4x In Exercises 7—12, identify the conic. 11 30. 29. —4 —4 31. Vertices: (O,±1); 32. Vertices: (±4, 0); Foci: (0,±3) Foci: (±6, 0) In Exercises 33—36, sketch the graph of the hyperbol Use a graphing utility to verify your graph. 33 9 64 0 35. 2 5y—4x 2 34 49 36 36.x2_y2= In Exercises 37—44, identify the conic. 6x+2v+90 37. 2 x — 38. y — 12v—8x+20=0 2 y+ 8 l +9y lOx— 250 x + 39. 2 r • Review Exercises In Exercises 1—6, match the equation with the correct graph. [The graphs are labeled (a), (b), (c), (d), (e), and (f).j (a) 4 112 82 In Exercises 17—20, sketch the graph of the parabola Use a graphing utility to verify your graph. 0 2 18. 8y+x 20.y_8x2=0 y 0 2 17.4x— = 19.l,v2+18x=0 In Exercises 2 1—24, write the equation of the specifie ellipse with center at the origin. 21. Vertices: (±5, 0); Foci: (±4, 0) 22. Vertices: (0, ±10); Foci: (0,±8) 23. Vertices: (0, ±6); Passes through: (2, 2) 24. Vertices: (±7, 0); Passes through: (0, ±6) (c) In Exercises 25—28, sketch the graph of the ellips Use a graphing utility to verify your graph. 2 2 + v 25. 4x (e) 26. 16 2 + 6v 2 = 18 x 8y 48 28.3 + 2 = 6 +4v 2 6x 27. 3 In Exercises 29—32, write the equation of the specifie hyperbola with center at the origin. 2 +2 1. 4x y 2 + 4 3. x 2 y 5. 4x 2 — 2 y = 4 2. 2 y = —4x 4 2 + )12 = 49 4 6. y 2 4 = — y=-2x :‘ + — 144 = 1 12. + = I = - = 13. Vertex: (0, 0); Vertical axis Passes through: (1, 2) 14. Vertex: (0, 0); Passes through: (4, —2) L 15. Vertex: (0, 0); Focus: (—6, 0) 16. Vertex: (0, 0); Focus: (0, 3) 6 16 In Exercises 13—16, write the equation of the specified parabola. Vertical axis I (—1, 0)’’(1 0) 2 + v 8. 16x 2 0 7. x 2 + 2Oy 49 yJ 4 2 4x In Exercises 7—12, identify the conic. 11 30. 29. —4 —4 31. Vertices: (O,±1); 32. Vertices: (±4, 0); Foci: (0,±3) Foci: (±6, 0) In Exercises 33—36, sketch the graph of the hyperbol Use a graphing utility to verify your graph. 33 9 64 0 35. 2 5y—4x 2 34 49 36 36.x2_y2= In Exercises 37—44, identify the conic. 6x+2v+90 37. 2 x — 38. y — 12v—8x+20=0 2 y+ 8 l +9y lOx— 250 x + 39. 2 Chapter 11 28 • Topics in Analytic Geometry In Exercises 59—62, sketch the curve represented by the parametric equations. 0 2 — 1 6x + 24y — 3 2 + l6y 0. 1 6x —11 =0 4y 1. 2 4x+8y — x 4 — 70 9y 18y+ .2. 2 lOx+ — x + — 16x+ 15=0 ± 2 3. 4x 4. 9x 2 y 2 — 72x+ 8)’ + 119 59. x y 0 Focus: (4, 0) Directrix: x = —3 18. Vertex: (2, 2); Directrix: y = 0 1 5t 2t + 5 — xt 2 2 61. + n Exercises 45—48, find a rectangular equation of the pecified parabola. 5. Vertex: (4, 2); 16. Vertex: (2, 0); 17. Vertex: (0, 2); = Focus: (0, 0) = 60. x = = 4t + 1 8 3r — 62.x= y 2 — 3 4t = — 1 In Exercises 63—72, sketch the curve represented by the parametric equations and write the correspond. ing rectangular equation by eliminating the parame. ter. Verify your result using a graphing utility. 63.x=/ 64.x=t y=./ n Exercises 49—52, find a rectangular equation of the pecified ellipse. 19. Vertices: (—3, 0), (7, 0); Foci: (0, 0), (4,0) 50. Vertices: (2, 0), (2, 4); Foci: (2, 1), (2, 3) 51. Vertices: (0, 1), (4, 1); Endpoints of the minor axis: (2, 0), (2, 2) 65.x=- 66.x=t y=t 67. x y y=— 68. x = y 52. Vertices: (—4, —1), (—4, 11); Endpoints of the minor axis: (—6,5), (—2,5) 69.x y = [n Exercises 53—56, find a rectangular equation of the specified hyperbola. 53. Vertices: (—10, 3), (6, 3); Foci: (— 12, 3), (8, 3) 54. Vertices: (2, 2), (—2, 2); Foci: (4, 2), (—4, 2) 55. Foci: (0, 0), (8, 0); Asymptotes:)’ = ±2(x 4) 71. x = 3 y = t t = t + 4 = 12 70.x== 2t + 3 72. x = I y=2 In Exercises 73—76, find two different sets of para metric equations for the given rectangular equation. — Asymptotes: y 56. Foci: (3, ±2); ±2(x — 3) In Exercises 57 and 58, complete the table for each set of parametric equations. 57. x=3t—2andy=7—4t -i oH 4 1 randy = 74.v10—x =2x 5x 76.y + 3 In Exercises 77—80, plot the point in the polar coordinate system and find three additional polar representations of the point, using —2 < 0 < 217. 23 79. ;- 58. x 73.y6x+2 ”x 2 75.y + 2 (, ) (,-) 78. (—2, 80. ) (/) In Exercises 81—84, plot the point given in the polar coordinates and find the corresponding rectangular coordinates for the point. 81. (s _) 82. (_3) Chapter 11 834 • Topics in Analytic Geometiy distinguishable permutations of In Exercises 25 and 26, find the number of the group of letters. 26. A, N, T, A, R, C, T, I, C, A 25. B, A, S. K, B, T, B, A, L, L sketch its graph. In Exercises 27—30, identify the conic and 2)2 + 1)2 (x (5)2 + ci+3) 2 28 9 27 4 121 36 0 y + 1 4 2x— 2 2 +y 30. x 2 = 16 x 29. y 2 for the graph of the conic. In Exercises 31—33, find an equation 33. 32. — — — — 4 10 4 12 foci (0, 0) and (0, 4), and asymptotes 34. Find an equation of the hyperbola with = ±x + 2. sented by the parametric equa In Exercises 35—37, (a) sketch the curve repre your graph, and (c) eliminate the tions, (b) use a graphing utility to verify ngular equation whose graph parameter and write the corresponding recta represents the curve. 37. x4lnt 36. x = 8 + 3t 35. x = 2t + 1 I., V = polar coordinates and find three In Exercises 38—41, plot (lie given point in IT. < 0 < 2 additional polar representations for —2 38. (8) 39. (, —) 41. (—3. 40. (_2,) 42. Convert the rectangular equation — — 8x 3y + 5 = —-) 0 to polar form. to rectangular form. 43. Convert the polar equation r — r equation. In Exercises 44—46, graph and identify the pola 44. 1 — 45. r 3 — 2 sin 0 46. r 2 + 5 cos 0 at (14, 0) and (2, ir) and one 47. Find a polar equation of the ellipse with vertices focus at the pole. four different positions. in how 48. A personnel manager has 15 applicants to fill applicants are qualified for many ways can this be done, assuming that all the any of the four positions? t be arranged in the proper order 49. On a game show, the digits 3, 4, and 5 mus ged correctly, the contes to form the price of an appliance. If they are arran of winning if the contestant tant wins the appliance. What is the probability knows that the price is at least $400? Chapter 11 Analytic Geometry IRUE/FALSE ITEMS F 1. F 2. F 3. F 4. F 5. F 6. F 7. F 8. F 9. F 10. equals the distance from that point to the directrit On a parabola, the distance from any point to the focus The foci of an ellipse lie on its minor axis. The foci of a hyperbola lie on its transverse axis. asymptotes. Hyperbolas always have asymptotes, and ellipses never have A hyperbola never intersects its conjugate axis. A hyperbola always intersects its transverse axis. l2y 0 defines an ellipse if a > 0. 2 2 + 6y The equation ax 2 = 10 defines a parabola if b 2 + bxy + 12y The equation 3x — —12. + sin 6) defines a hyperbola. If (r, 6) are polar coordinates, the equation r = 2/(2 3 Parametric equations defining a curve are unique. REVIEW EXERCISES for use in a Practice Test. Blue problem numbers indicate the authors’ suggestions la, give its vertex, In Problems 1—20, identify each equation. If it is a parabo center, vertices, its give ola, hyperb a is it if give its center, vertices, and foci; 1 2 y —16x 4. 7. 4y4 x + 2 36 10. 2 9x + 4y 13. 16. x =4 4y-—4 —8x 2 y + 16x + 18y 2 2 + 9y 4x 19. =23 y x +8y 4 18x 9 + 2 — = — 11 and directrix; if it is an ellipse, and asymptotes. focus, foci, 2. y 2 16x 3• 5 l +x 2 y _ 16 25 6. 8. x 9 — 2 3y = 9. 2)’ 12. --2 y 4y=x 2 2 — 2 2 + 9y 4x 4x 11. 2 x 14. 4=0 y x 8x—4y+ 4 + 2 + 15. 17. 32=0 x 16x+16y+ 2 4 — 18. 20. y 2x—2y=1 — 2 x — — = y 8 — 2 4x = lSy = 11 19=O y 3x—16y+ 4 + 2 — 16x — ed. Graph the equation. in Problems 21—36, obtain an equation of the conic describ 30. Parabola; focus at (3, 6); directrix the line 21. Parabola; focus at (—2, 0); directrix the line 8 y= x2 22. 23. 24. Ellipse; center at (0,0); focus at (0,3); vertex at (0,5) Hyperbola; center at (0, 0); focus at (0, 4); ver tex at (0, —2) Parabola; vertex at (0, 0); directrix the line y = —3 25. Ellipse; foci at (—3, 0) and (3, 0); vertex at (4, 0) 26. Hyperbola; vertices at (—2,0) and (2,0); focus at (4, 0) 27. Parabola; vertex at (2, —3); focus at (2, —4) 28. Ellipse; center at (—1,2); focus at (0,2); vertex at (2,2) 29. Hyperbola; center at (—2, —3); focus at (—4, —3); vertex at (—3, —3) 31. Ellipse; foci at (—4, 2) and (—4, 8); vertex at (—4, 10) 32. Hyperbola; vertices at (—3, 3) and (5, 3); focus at (7, 3) 33. Center at (—1, 2); a = 3; c parallel to the x-axis 34. Center at (4, —2); a = 1; c parallel to the y-axis 35. line Vertices at (0, 1) and (6, 1); asymptote the 3y + 2x 9 0 = 4; transverse axis = 4; transverse axis — 36. line Vertices at (4, 0) and (4, 4); asymptote the y + 2x —10 0