The Census Bureau projection of female life expectancy at age 65 in the United States are summarized in the following table (x=0 corresponds to the year 2000):
Year (x) Years beyond 65 (y)
0 19.5
10 20
20 20.6
30 21.2
40 21.8
50 22.4
a) Find an equation for the trend line using the method of least squares.
b) Use your trend line to predict the life expectancy at 65 of a female in the year 2070 (x = 70).