V. Zabrocki - 1
08/26/2002
Finding the Line of Best Fit Using the TI-86
Objective: To draw the scatter diagram for the given data, find the equation of the line of
best fit and graph the line of best fit on the scatter diagram.
x 3 5 7 9 11 13 Data
y 0 2 3 6 9 11
(Clear all previously saved functions)
To enter the data:
2nd STAT
F2: Edit
To clear previous entries, highlight the column header xStat then clear then enter.
Do the same with the yStat column.
Key in values for x in the xStat column. When you hit enter the cursor moves to the
next x value.
Key in values for y in the yStat column.
The fStat column should contain an entry of 1 for each (x, y) value. Delete any extra
1’s by highlighting them and then Del
Exit
To create the scatter diagram:
To graph scatter diagram:
2nd STAT
F3: PLOT
F1: PLOT 1 This will set-up the type of graph.
Highlight ON then Enter
Type: F1: SCAT
xlist Name = xStat
ylist Name = yStat
Mark: F1 will select the box as a marker. Choose F2 or F3 for other markers.
Exit
Be sure the other plots are OFF. If they’re not, select them by using F2 or F3 and
highlight OFF and then Enter
Exit
2nd STAT
F4: Draw
CLEAR (removes the menu bars so the whole graph is visible)
Exit (brings back menu)
