
Answer:
 There were 150 student tickets and 200 adult tickets sold
Step-by-step explanation:
Let s and a represent the numbers of student and adult tickets sold, respectively. Then the two equations are ...
 s + a = 350 . . . . . . total number of tickets sold
 12.50s + 16.00a = 5075 . . . . . .total value of tickets sold
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Solution
The first equation lets us write an expression for s:
 s = 350 - a
We can substitute this into the second equation:
 12.50(350 -a) +16.00a = 5075
 3.50a + 4375 = 5075 . . . . . . . . . simplify
 3.50a = 700 . . . . . . . . . . . . . . . . . subtract 4375
 a = 200  . . . . . . . . . . . . . . . . . . . . . divide by 3.50
There were 200 adult tickets and 150 student tickets sold.