1. A set of linear equations involving the two variables A solution is the intersection of the two lines. One of three things can happen: 11.1 Systems of Linear Equations

2. Example 1

3. Example 2

4. A chemist wants to mix a 20% saline solution with a 40% saline solution to get 1 liter of a 26% solution. How much of each should she use? (1 liter = 1000 ml) += Example 3

5. A boat travels downstream for 20 miles in 1 hour. It turns around and travels 20 miles upstream (against the current) in 1 hour and 40 minutes. What is the boat’s speed and how fast is the current? 20 miles Example 4