College Algebra, 4th Edition

Applying the Concepts

1. 105.

   1. Initial expenses

   2. Breaking even

   3. $640

   4. $P=(695/8)n-750$

2. 107. ${\displaystyle \frac{1}{10}}$

3. 109. He should trim the hedge every 10 days.

4. 111.

   1. x: time in weeks; y: amount of money after x week in the account; $y=7x+130$

   2. Slope: weekly deposit in the account; y-intercept: initial deposit

5. 113.

   1. x: number of months since purchase of the refrigerator; y: amount owed after x months; $y=-15x+600$

   2. Slope: monthly payment; y-intercept: initial charge

6. 115.

   1. x: number of years after 2010; y: life expectancy of a female born in the United States in the year $x+2010;y=0.17x+80.8$

   2. Slope: rate of increase in the life expectancy of a female born in the United States; y-intercept: ­current life expectancy of a female born in the United States in 2010

7. 117. No extra ...