Advertising revenue for newspapers in the United States for the years 1985 through 1999 is
approximated by the model where R is revenue in billions of
dollars and t represents the year with
2 R = −1.03 + 7.11t − 0.38t
t = 5 corresponding to the year 1985. In what year will
revenue be maximum?
+36916 Is this part of your equation written correctly? I think one of these terms should be t^2 ???
7.11t − 0.38t <<<<<<<<-------- probably this one?
+36916 2 R = −1.03 + 7.11t − 0.38t^2
Max will be at - b/2a = - 7.11/(2*(-.38)) = 9.355 yrs since 1985 is t 5 1989 will be the year
