SOLUTION: Please help me on this problem...I know how to go to the edit screen and insert the data in the calculator but im not sure what to do next.. I would like to know how to do it on pa

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Question 460930: Please help me on this problem...I know how to go to the edit screen and insert the data in the calculator but im not sure what to do next.. I would like to know how to do it on paper also.
For the data below:
year, x / number of electroically filed tax returns, y(in millions)
1995, 0 / 11.807
1997, 2 / 19.136
1999, 4 / 29.349
2001, 6 / 40.245
2003, 8 / 52.945
2005, 10 / 68.476
a)find a linear model using the years 0 and 4
b)find a linear model using the graphing calculator.
c)what is the correlation coefficient?
d)use your model to predict the numbers for 2010.
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
a)find a linear model using the years 0 and 4
Find the equation of a line through the points

(0,11.807) and (4,29.349)

m = %28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29=%2829.349-11.807%29%2F%284-0%29+=+4.3855

then use 

y - y1 = m(x - x1)

y - 11.807 = 4.3855(x - 0)

y - 11.807 = 4.3855x

         y = 4.3855x + 11.807

------------------------------------

b)find a linear model using the graphing calculator.
press CLEAR
press STAT
press the right arrow key to highlight CALC
press 4
You will see 

               LinReg(ax+b)

Press ENTER
You will see
               LinReg 
                y=ax+b
                a=5.6524
                b=8.731
                rē=.9861609225
                r=.9930563541

The equation of the line is y = 5.6524x + 8.731

---------------------------------------------

c)what is the correlation coefficient?
That's the value of r, which is r=.9930563541

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d)use your model to predict the numbers for 2010.
1995, 0 
1997, 2
1999, 4
2001, 6 
2003, 8 
2005, 10 

Extend this list by 2's:

2007, 12
2009, 14
2011, 16

Since 2010 is halfway between 2009, 14 and 2011 16,
we must have 2010 as 15.

So we substitute 15 for x in the formula:

y = 5.6524x + 8.731
y = 5.6524(15) + 8.731
y = 93.517

Edwin