Answer:
x = the number of years sought
13,700 students at College A with an expected increase in enrollment of 800 students per year
in x years there will be 13700+800x
28,700 students at College B with a projected decline in enrollment of 700 students per year.
in x years there will be 28700-700x
we write the following equation
13700+800x=28700-700x
800x+700x=28700-13700
1500x= 15000
x= 10
in 10 years colleges will have the same number of enrollments
in 10 years College A: 13,700+800*10=21,700
in 10 years college B: 28700-700*10 = 28700-7000=21,700