Scatter Plots on the Ti-83

SCATTER PLOTS ON THE TI-83

1. To clear Y=

Press Y= and clear all equations

2. To turn on Stat Plots (a step that does not have to be done every time)

Press 2nd Y= ENTER Change Plot1 to On, everything else should stay the same *You do not have to have your stat plots on unless you want to see the actual points that you have entered in L1 and L2. If you wait to get your equation, then you can make predictions with just your equation in y=.

3. To turn Diagnostics on (a step that does not have to be done every time)

Press 2nd 0 (Catalog), x 1 , arrow down 8-9 times (may differ per calculator), ENTER

4. To clear lists of data

Press STAT 1 (Edit...) ENTER You should be on the screen to enter data. Arrow up to L1. Press CLEAR. Arrow down and the data should disappear. Repeat for L2. (Do NOT hit delete, use CLEAR!)

5. To enter data

Press STAT 1 ENTER. Enter x values in for L1, y values in for L2.

6. To see scatter plot on screen

Press ZOOM 9 (ZoomStat)

7. To calculate line of best fit (trend line, regression line)

Press STAT arrow to CALC 4 (LinReg) ENTER Data should show up on screen. You can write equation in y = mx + b form (calculator uses a instead of m)

8. To draw trend line on graph (need this for predictions)

Press Y= VARS 5 (Statistics) arrow to EQ, #1 (RegEq) ENTER GRAPH (after equation is on screen)

9. To make predictions

2nd WINDOW (TblSet), put the x value given in for TblStart then go to 2ND GRAPH (Table) and you should see the corresponding y-value. (Or, if it asks for the y-value, given the x-value, you could just do 2nd trace value, x = the number you are looking for and it will give you y at the bottom.)

To find a x-value, given the y-value, then go to y = and put into Y2 the number you have. Go to your graph and you should see two lines. Find the intersection between the two. (2nd trace intersect, enter, enter, enter)