1. Using the Quadratic Formula to Solve Quadratic Equations Section 7.5

2. Lehmann, Intermediate Algebra, 4ed Section 7.5Slide 2 Using a Quadratic Function to Model a Situation Modeling with a Quadratic Function Example Annual consumption of bottled water in the United States has been increasing since 1990 (see Table). Let f (t) be bottled-water consumption (in billions of gallons) in the year that is t years since1990. A possible equation of f is 1. Verify that f models the data well. 2. Predict when annual consumption will reach 11 billion gallons.

3. Lehmann, Intermediate Algebra, 4ed Section 7.5Slide 3 Using a Quadratic Function to Model a Situation Modeling with a Quadratic Function Example Use a graphing calculator to create a scattergram Solution Continued

4. Lehmann, Intermediate Algebra, 4ed Section 7.5Slide 4 Using a Quadratic Function to Model a Situation Modeling with a Quadratic Function ExampleSolution Continued

5. Lehmann, Intermediate Algebra, 4ed Section 7.5Slide 5 Using a Quadratic Function to Model a Situation Modeling with a Quadratic Function Example The inputs –27.53 and 20.03 represents the years 1962 and 2010 The estimate of 1962 is a result of model breakdown We predict that it will be 2010 when bottled-water consumption reaches 11 billion gallons Solution Continued