Answer:
Number of tickets sold to students and adults are 200 and 300 respectively.
Explanation:
Let, the number of student tickets = x and number of adult tickets = y.
As, there are total number of 500 seats in the theater, we have,

Also, the price of the tickets is $5 per student and $8 per adult.
Since, the total sales are of $3400. We get,

So, the system of equations is given by,
x+y=500 ........................... (1)
5x+8y=3400 ..........................(2)
Multiply equation (1) by 5 and subtract with equation (2), we get,
3y = 900 i.e. y= 300
So, x=500-y implies x=500-300 i.e. x= 200
Hence, the number of tickets sold to students and adults are 200 and 300 respectively.