During the period 1985–2012, the projected enrollment B (in thousands of students) in public schools and the projected enrollmen
t R (in thousands of students) in private schools can be modeled by B = –18.53t2 + 975.8t + 48,140 and R = 80.8t + 8049, where t is the number of years since 1985.
The equation that models the difference in the projected enrollments for
public schools and private schools as a function of the number of years
since 1985 is B - R = (-18.53t^2 + 975.8t + 48140) - (80.8t + 8049) = -18.53t^2 + 975.8t + 48140 - 80.8t - 8049 = -18.53t^2 + 895t + 40091
