Remember that
the average rate of change is equal to
[tex]\frac{f(b)-f(a)}{b-a}[/tex]where
f -----> is the population in thousands (dependent variable)
a and b -----> year (independent variable)
Part 1)
Average rate of change from 2000 to 2009
so
a=2000
b=2009
f(a)=f(2000)=844
f(b)=f(2009)=856
substutute the given values
[tex]\frac{856-844}{2009-2000}=\frac{12}{9}=\frac{4}{3}=1.3333[/tex]the average rate of change is 1.3333 thousands people per year
Part 2
Average rate of change from 2009 to 2015
we have
a=2009
b=2015
f(a)=f(2009)=856
f(b)=f(2015)=810
substitute
[tex]\frac{810-856}{2015-2009}=\frac{-46}{6}=-\frac{23}{3}=-7.6667[/tex]average rate is -7.6667 thousands people per year