a. Use the two points whose coordinates are shown (6,12) and (10,10) to find the​ point-slope form of the equation of the line that models the percentage of adults on​ diets, y, x years after 1987.

b. Write the equation in part​ (a) in​ slope-intercept form. Use function​ notation, where​ f(x) is the percentage of adults on diets x years after 1987.

c.Use the linear function to predict the percentage of adults on​ weight-loss diets in 2007.