A study by the Partnership for a Drug-Free America indicated that, in 1998, 42% of teens in grades 7 through 12 had recently used cigarettes. A similar study in 2005 indicated that 22% of such teens had recently used cigarettes.
(a) Write a linear equation that relates the percent of teens y to the number of years after 1998, x.
(b) Find the intercepts of the graph of your equation.
(c) Do the intercepts have any meaningful interpretation?
(d) Use your equation to predict the percent for the year 2019. Is this result reasonable?

Question

A study by the Partnership for a Drug-Free America indicated that, in 1998, 42% of teens in grades 7 through 12 had recently used cigarettes. A similar study in 2005 indicated that 22% of such teens had recently used cigarettes.
    (a) Write a linear equation that relates the percent of teens y to the number of years after 1998, x.
    (b) Find the intercepts of the graph of your equation.
    (c) Do the intercepts have any meaningful interpretation?
    (d) Use your equation to predict the percent for the year 2019. Is this result reasonable?