The local high school sold 216 tickets to a play. They sold adult tickets for $7 and student tickets for $4. The box office collected a total of $1269.

Which system of equations could be used to determine the number of adult tickets, a, and the number of student tickets, s, sold?

a + s = 216

7a + 4s = 1269

a + s = 216, , 7a + 4s = 1269,

a + s = 1269

7a + 4s = 216

a + s = 1269, , 7a + 4s = 216,

a + 216 = s

7a + 4s = 1269

a + 216 = s, , 7a + 4s = 1269,

a + s = 216

4a + 7s = 1269

a + s = 216, , 4a + 7s = 1269,