490 CHAPTER 7 Rational Expressions and Applications
EXERCISES 71–80FOR INDIVIDUAL OR GROUP WORK
In these exercises, we summarize the various concepts involving rational expressions.
Work Exercises 71–80 in order.
Let P,Q,and R be rational expressions defined as follows:.71.Find the value or values for which the expression is undefined.
(a)P (b)Q (c) R
72.Find and express in lowest terms.
73.Why is not defined if?
74.Find the LCD for P, Q, and R.
75.Perform the operations and express in lowest terms.
76.Simplify the complex fraction.
77.Solve the equation.
78.How does your answer to Exercise 71help you work Exercise 77?
79.Suppose that a car travels 6 miles in minutes. Explain why Prepresents the
rate of the car (in miles per minute).
80.For what value or values of xis ?R=^40771 x+ 32P+Q=RP+Q
R^P+Q-R1 P#Q 2 ,R x= 0
1 P#Q 2 ,R
R=
4 x
x^2 + 4 x+ 3Q=
5
x+ 1P= ,
6
x+ 3,RELATING CONCEPTS
1.Find the numerical value of for (a) and (b).2.Find any values for which is undefined. Write your answer with the symbol.3.Write four rational expressions equivalent toWrite each rational expression in lowest terms.Multiply or divide. Write each answer in lowest terms.Find the least common denominator for the fractions in each list.
- 2 r+ 1
2 r^2 - 7 r- 15
r+ 1
2 r^2 + 7 r+ 6,- 7
30 p^5
21
25 p^3,- 3
10 p^2
,x^2 - 10 x+ 25
9 - 6 x+x^2#x-^3
5 - x4 a^2 + 9 a+ 2
3 a^2 + 11 a+ 10
,4 a^2 + 17 a+ 4
3 a^2 + 2 a- 56 k^2 - k- 2
8 k^2 + 10 k+ 3#^4 k
(^2) + 7 k+ 3
3 k^2 + 5 k+ 2
51 d- 22
9
,
31 d- 22
5
6 a^2 +a- 2
2 a^2 - 3 a+ 1
- 15 x^6 y^4
5 x^4 y
6 x- 5
2 x+ 3.Z3 x- 1
x^2 - 2 x- 8r=- 2 r= 46 r+ 1
2 r^2 - 3 r- 20TEST
CHAPTER 7
View the complete solutions to
all Chapter Test exercises on
the Video Resources on DVD.
Step-by-step test solutions are found on the Chapter Test Prep Videos
available via the Video Resources on DVD, in , or on
(search “LialBeginningAlgebra”).CHAPTERhttp://www.ebook777.com
http://www.ebook777.com