### Exercise 1

*((Reference))* Solve using graphing:

#### Solution

inconsistent

### Exercise 2

*((Reference))* Solve using graphing:

#### Solution

### Exercise 3

*((Reference))* Solve using substitution:

#### Solution

### Exercise 4

*((Reference))* Solve using addition:

#### Solution

### Exercise 5

*((Reference), (Reference))* Solve using either substitution or addition:

#### Solution

inconsistent

### Exercise 6

*((Reference), (Reference))* Solve using either substitution or addition:

#### Solution

### Exercise 7

*((Reference))* The sum of two numbers is 43 and the difference of the same two numbers is 7. What are the numbers?

#### Solution

18 and 25

### Exercise 8

*((Reference))* A chemist needs 80 ml of an 18% acid solution. She has two acid solutions, A and B, to mix together to form the 80-ml solution. Acid solution A is 15% acid and acid solution B is 20% acid. How much of each solution should be used?

#### Solution

### Exercise 9

*((Reference))* A parking meter contains 32 coins. If the meter contains only nickels and quarters, and the total value of the coins is

#### Solution

17 nickels and 15 quarters

### Exercise 10

*((Reference))* A person has $15,000 to invest. If he invests part at 8% and the rest at 12%, how much should he invest at each rate to produce the same return as if he had invested it all at 9%?

Comments:"Reviewer's Comments: 'I recommend this book for courses in elementary algebra. The chapters are fairly clear and comprehensible, making them quite readable. The authors do a particularly nice job […]"