1. Sec. 2-4: Using Linear Models

2. Scatter Plots 1.Dependent Variable: The variable whose value DEPENDS on another’s value. (y) 2.Independent Variable: The variable that is “controllable” that can change another variable’s value. (x)

3. 3.Scatter Plot: A graph of ordered pairs that represent 2 different sets of data. 4.Trend Line: (line of best fit) A line that APPROXIMATES a relationship between data. (Just write an equation of the line the data represents use 2 points and y-y = m(x-x).) You can use trend lines to make predictions about your data in the future.

4. Using the calculator as a tool to obtain linear models. We will be using the STAT key on the calculator to enter our data. L 1 will represent the x data. L 2 will represent the y data. 2 nd Y= to turn your “stat plot” ON to scatter plot. ZOOM #9 (Stat)

5. Using the calculator to create a Trend Line STAT and select CALC. Select #4 LinReg(ax + b) & hit ENTER. Hit the Y= Hit VARS & select #5 “Statistics” and select “EQ” (this types your equation into the y= screen) Hit GRAPH Your Trend Line now appears on your scatter plot.

6. To make predictions on the calculator: You MUST be able to “see” the value you are looking for….you may need to adjust the WINDOW screen. Hit 2 nd TRACE select “value” and type in the value you need to predict about.