Solutions to “You’ve Got Problems”
All of the answers to the problems that haunted you throughout the book are listed here, organized by chapter. The important steps are all shown, unless the skill needed to complete a problem was already discussed in a previous chapter. For example, once you learn how to do u-substitution in Chapter 15, I no longer focus on its details if problems in subsequent chapters require u-substitution as a component of their answers. If I didn’t do that, this appendix would be a book unto itself!
1. 6x + 9y = 11. Don’t forget that 6x has to be positive to be in standard form. You may need to multiply everything by –1.
2. 2x – 3y = 6. You can treat (0,–2) as a point or use it as the y-intercept, so ...