Instructions For MWMilton

 

Entering a Table and Finding the Best-Fitting Line

 

Directions: Use the computer to plot the following table and draw the best fitting line through the data.

 

X

-4

-2

0

2

4

Y

1.2

2.8

5.3

6.7

9.1

 

Step 1 Enter the table.

 

In the Graphing Calculator page of  MWMilton, enter each x- and

 y-value into the table located on the left side of the screen.

One-by-one, click the cursor in a box and type in the value.

 

 

Step 2 Select an appropriate graphing window.

 

Since the table has minimum x-value -4, maximum x-value  4, minimum y-value  1.2, and maximum y-value  9.1, one possible graphing window is

[-6, 6] by [0, 12]. Choices for the X-scale and Y-scale values are automatically done for you. Enter these values into the Graphing Window. Use the cursor to move from box to box. First, highlight the value -10 that is to be changed, delete it, and then enter the new value -6; continue until all values have been changed.

 

Step 3 Plot the table.

 

To have the computer plot the table, click on the Plot button in the Table Controls part of the screen. Afterwards, the table will be plotted in the graphing window on the right side of the screen as shown in the next figure.

 

 

 

Step 4  Draw the line/curve that best fits the data.

 

To have the computer draw the best fitting line/curve through the data, click on the button labeled Linear that is located in the lower left side

of the screen in the Table Fit Models section. (You may choose other models for other problems.) Afterwards, the best fitting line will also be plotted in the graphing window as shown in the next figure.

 

 

Step 5 Formula of the best fitting line.

 

In the Output Screen window located near the top of the screen, scroll upwards to see the formula of the best fitting line and the correlation coefficient. If the formula is not displayed, click again on the Linear button in the Table Fit Models; the formula should now appear in the Output Screen window.

 

 

For this problem, the formula of the fitting line is

 y = f(x) = 0.985x + 5.02

 

 

 

 

 

 

Step 6 Get coordinates of points on the graph.

 

To get coordinates of points on the fitting line/curve, right click anywhere in the graphing window. A new window appears that has Actions as an option.

Left click on Actions; then left click on Get Coordinates. See the next figure.

 

 

 

 

            Afterwards, a Coordinate box appears on the screen. This box can be moved: left click in the upper blue part of the box and drag it to move it. See the next figure.

 

 

Next click on any point on the line/curve and the (x,y) coordinates of the point will be displayed in the coordinate box.

 

Step 7 Get a printout.

 

Option 1: There is a print option located in the Workbook tab at the top of the screen.

Note that before printing, you must sometimes change the paper orientation from Portrait to Landscape to print the entire output.

 

 

Option 2: To print only the scatter plot of the table and the fitting line/curve, click on the Big Graph button on the lower right side of the window. The following figure should appear.

 

 

 

 

 

Next, click on the Workbook tab at the top of the screen and select the print option. Note that before printing, you must sometimes change the paper orientation from Portrait to Landscape to print the entire output.

 

Option 3: To copy the MWMilton page to another application like MS Word, you must first save the output to the clip board.

 

 

Then open MS Word and use the Paste command to add the MWMilton output to a document. You can then print the document as usual.