1. Pre Assignment Sunday TI Graphing Calculator Section 1.4: Linear Functions & Models

2. Plot the curve for values of x from -4 to 3. Example 1

3. Use the TI to solve the equation shown below: Example 2

4. The data below gives the average ATM surcharge for various years. Use the TI to look at a scatterplot of the data below. Let x represent the years since 1990. Comment on its general shape. Example 3 Year 19982000200220042006 Surcharge 0.891.341.381.391.64

5. Suppose C(n) is the cost in ($million) for a company to produce n hundred widgets. (a)What are the input & output of the model? (b)What are the input & output variables? (a)What are the input & output units? Example 4

6. Suppose C(n) is the cost in ($million) for a company to produce n hundred widgets. (d) Write a sentence interpreting C(2.75) = 1.8. Example 4

7. Suppose C(n) is the cost in ($million) for a company to produce n hundred widgets. (e) Write the sentence “It costs $2.7 million for the company to produce 315 widgets” using the function notation of this model. Example 4

8. In 1982 the population of a small town was 5000 people. In 1986 the population had grown to 15000 people. (a)Let x represent the number of years since 1980 and find a linear model for the population of this town. (b)Interpret the slope of your model in context. (c)Interpret the y-intercept of your model in context. Example 5

9. The total number of bankruptcy filings x years after 1996 can be modeled by filings. (a)Interpret the slope of this model. (b)Interpret the B-intercept of this model. (c)Calculate the number of bankruptcy filings in 2000. Example 6

10. The table below shows the income tax paid by a certain individual in various years. Look at a scatterplot of the data, and if it seems appropriate, find a linear model for the data. Let x = years since 1990. Example 7 Year19961998200020022004 Taxes ($)25413081361541574703

11. The table below shows the cost to purchase x printed sweatshirts from a certain company. (a)Find a linear regression model for the data. (b)Interpret the slope of you model. (c)Estimate the cost to purchase 310 shirts and 500 shirts. Which estimate do you trust more? Why? Example 8 # shirts50150250350 Cost ($)250500700950