True! they are corresponding angles.
A would be (-3, 6).
B would be (-6, 3).
Anytime something is asking you to reflect off of the Y-axis, you put the original but flipped. Also, your answer will always be straight across vertically.
We can solve this by setting up a proportion:
12 seeing the play/ 72 students = 210 seeing the play/ x students
We can cross multiply to solve for x:
(12)x=(72)(210)
12x=15,120
x=1,260 students who attend the school