7.3 Simplify each complex fraction.
21. 22. 23. 24.
7.4 Solve each equation.
25. 26.
27. 28.
29.Concept Check Professor Dan Abbey asked the following question on a test: What is
the solution set of? Only one student answered it correctly.
(a)What is the solution set?
(b)Many students answered. Why is this not correct?
30.Explain the difference between simplifying the expression and solving the
equation.
31.Concept Check Which graph has vertical and horizontal asymptotes? What are their
equations?
A. B. C. D.
4
x+
1
2 =
1
3
4
x+
1
2 -
1
3
1 - q, q 2
x+ 3
x+ 3 =^1
5
x+ 2
+
3
x+ 3
=
x
x^2 + 5 x+ 6
2
k- 1
-
4 k+ 1
k^2 - 1
=
- 1
k+ 1
- 5 m
m+ 1
+
m
3 m+ 3
=
56
6 m+ 6
1
t+ 4
+
1
2
=
3
2 t+ 8
x-^2 - y-^2
x-^1 - y-^1
3
p
- 2
q
9 q^2 - 4 p^2
qp
2
m- 3 n
1
3 n-m
3
t
+ 2
4
t
- 7
y
x
0
y
x
0
y
x
0
y
x
7.5
32.An equation of a law from physics is given in the form Find Aif and
Solve each formula for the specified variable.
- for m ( physics) 34. for M (electronics)
Solve each problem.
35.An article in Scientific Americanpredicted that, in the year 2050, about 23,200 of the 58,000
passenger-km per day in North America will be provided by high-speed trains. If the traffic
volume in a typical region of North America is 15,000, how many passenger-kilometers per
day will high-speed trains provide there? (Source:Schafer, Andreas, and David Victor, “The
Past and Future of Global Mobility,” Scientific American.)
36.A river has a current of 4 km per hr. Find the rate of
Herby Assad’s boat in still water if it goes 40 km
downstream in the same time that it takes to go 24 km
upstream.
37.A sink can be filled by a cold-water tap in 8 min and by a hot-water tap in 12 min. How
long would it take to fill the sink with both taps open?
38.Jane Riggs and Jessica Ross need to sort a pile of bottles at the recycling center. Working
alone, Jane could do the entire job in 9 hr, while Jessica could do the entire job in 6 hr.
How long will it take them if they work together?
m=
Mn
M+m
F=
GMm
d^2
C=10.
(^1) A= (^1) B+C (^1). B= 30
drt
Upstream 24
Downstream 40
x- 4