Final answer:
The equation that represents the enrollment, y, in terms of x years since 1990 is y = mx + b. In this equation, 'm' represents the slope and 'b' represents the y-intercept.
Step-by-step explanation:
The equation that represents the enrollment, y, in terms of x years since 1990 is:
y = mx + b
In this equation, 'm' represents the slope of the line, which is the rate of change in enrollment over time. 'b' represents the y-intercept, which is the initial enrollment at x = 0 (in this case, the enrollment in 1990).