Use your TI-84

Press stat 1 
Put the X values in L1 and the Y values in L2

Press stat 
Press the right arrow to highlight CALC
Press 4

      LinReg(ax+b) 
Xlist:L1
Ylist:L2
FreqList:
Store RegEQ:Y1 <--to get Y1 here Press vars rt. arrow to hilite Y-vars 1 1
Calculate      <--down arrow to hilite Calculate 

Press enter

        LinReg  
y=ax+b
a=         <--there will be a number here, that's "a"
b=         <--there will be a number here too, that's "b" 
r²=        <--there will be a number here
r=         <--there will be a number here, that's the reg. coeff.

Substitute a and b in y=ax+b, that is the regression equation.

Press 2nd then y= (upper left corner key of calculator)

Plt1 Plot2 Plot3
On Off            <--highlight "On"
Type:             <--highlight 1st icon (looks like scatterplot)
Xlist:L1
Ylist:L2
Mark:             <--highlight whichever icon you want on scatterplot
Color:            <--pick a color if your calculator is a newer model and
                     has this

Press zoom       

Use down arrow key to scroll to ZoomStat
Press enter

You will see both the regression line and the scatter plot.

To find the values on the scatter plot press 2nd trace 1

type in each value of X and see the scatter plot point highlighted.

To find values on the regression line press zoom and scroll to zoomfit

press enter

press 2nd trace 1
type in value see value of Y on the regression line.

To draw this on your paper to turn in, get points on the
regression line and plot them on your graph paper.

If you have trouble tell me in the space below and I'll get
back to you by email. No charge ever.

Edwin