[tex]x[/tex] - number of years passed since 1960
[tex]y[/tex] - time in minutes
A line [tex]y=mx+n[/tex] passes through the points (0,3.91) and (20,3.81).
Find slope.
[tex]m= \frac{3.81-3.91}{20-0}= \frac{-0.1}{20}=-0.005[/tex]
Find [tex]y[/tex]-intercept.
[tex]y=mx+n
\\3.91=-0.005 \times 0+n
\\n=3.91[/tex]
The equation of line is
[tex]y=-0.005+3.91 [/tex]
