559 tickets were sold 59 more student tickets were sold than adult tickets how many adult tickets were sold

Let s = number of student tickets and a = number of adult tichets;

We have the equation: s + a = 559 and s = 59 + a;

Then, we solve the equation: 59 + a + a = 559;

59 + 2a = 559;

2a = 500;

a = 500/2;

a = 250;

s = 59 + 250;

s = 309;