b. They are the same shape. They are reflections of each
other over the y-axis. 4a. direct; y= -3 x b. inverse;
xy = -48 5a. Direct; the ratio of the total cost to the
number of sweaters bought is a constant, 35. b. Inverse;
the product of your speed and the time spent walking is a
constant, 5.
Lesso n Check 1. xy= -51 2. 120 lb
- direct; y = -2x 5. yes; 15 6. Never; the equation is
of the form y = f , and 0 is not in the domain of the
function. - The heavier must be closer because the product of the
weight and its distance from the fulcrum is a constant. - No; it will only vary inversely if the product of the
number of pencils purchased times the price per pencil
is a c o n stan t.
Ex e r c i s e s 9. xy= 18 11. x y = 56 13. xy- 24 15. 3 h - yes; 3 64. no 65. yes; 66. yes; |
Lesson 11-6 pp. 6 9 8 -7 0 4
Go t It? 1. xy = 54 2. 7.5 ft
17.19.21.- Y
J—7 0y
-II 0X(^3) / - -------
- direct; y = § 27. inverse; xy= 72 29. Inverse
variation; the product of cost per person times the
number of people is a constant. 31. 256; xy = 256
33. 1; x y = 1 35. 5 37. Direct; the ratio f is a
constant, 3. 39. Direct; the ratio f is a constant, 2 tt.
41a. The value of y doubles, b. The value of y is cut
in half. 43. direct; y = 0.4x; 8 45. inverse; xy = 48; 0.5 - No; the equation of the graph is of the form
y = — 2x + b. 49. 4; s ( ^ ) 2 = ^ = k, so s =
51.8 53. -2 5 54. no solution 55. - |