Tell w hether each table represents a direct variation or an inverse variation
Write an equation to model the data. Then complete the table.on *—43
Mi ♦ f
10 4 0.4 28 1.6^30(^20) ■J |1.2 84 4.8^10
(^8) 3.2 m 63 H^96
(222) 46. Physics Boyle’s Law states th a t volum e Vvaries inversely w ith pressure P for any
gas at a co n stan t tem p eratu re in an enclosed space. Suppose a gas at co n stan t
tem p eratu re occupies 15.3 L at a pressure of 40 m m of m ercury. W hat equ atio n
m odels this situation?
- Error Analysis W hen graphing a certain function, Pedro sees th a t th e value of y
decreases by 2 w henever th e value of x increases by 1. Pedro says th a t th e graph
represents an inverse variation. Is he correct? Explain.
f t Challenge 48. Write an equation to model each situation.
a. y varies inversely with th e fourth pow er of x.
b. y varies inversely w ith th e fourth pow er of x a n d d i r e c t ly w i t h z. - Physics The intensity of a so u n d s varies inversely w ith th e square of the distance
d from th e sound. This can be m od eled by th e eq u a tio n sd2 = k, w here k is a
constant. If you decrease your d istance from th e source of a so und by half, by w hat
factor will th e intensity of th e so u n d increase? Explain your reasoning.
^AT/ACTSt a n d a r d i ze d Test Pr ep
- W hat is th e value of -
6 RI D D ED RESPON SE(64)“ —- The diagram shows two squares. The area of th e n o n sh a d e d region
is 4x2 + 16x + 16. The area of th e sh ad ed region is 5x2 + 14x + 9.
W hat is |a + b|? - W hat is th e value of - -*-----------a + b x------------►
a + bxMixed Review
Solve each equation. If there is no solution, write no solution.53.^2 _^3 54. =± + 1 = 1
d + 5 d — 5
Get Ready! To p r e p a r e f o r Lesso n 11 -7, do Exercises 56-59.
Graph each function.- /(x ) = x - 8 57. g(x) = x2 + 3 58. y = 3X
See Lesson 11-5.- r r ^ + 2 = : m — 4 m - 45m
4* See Lessons 4-4,7-6, and 9-1.- / (x ) = 2x + 1
704 Chapter 11 Rat io nal Expressions and Funct ions