88.20 Chapter 5. Special Techniques for Linear Equations. Exercises at page 146

88.20.1 problem 1
88.20.2 problem 2
88.20.3 problem 3
88.20.4 problem 4
88.20.5 problem 5
88.20.6 problem 6
88.20.7 problem 7
88.20.8 problem 8
88.20.9 problem 9
88.20.10 problem 10
88.20.11 problem 11
88.20.12 problem 11