I’m not sure how the chart works but here’s how to solve the problem. 
First creat two inequalities with the values given using x as the number of student ticked and y as non student. 
X + y = 292 tickets 
Notice how this measures only the tickets
The next equation is the cost and total earnings. 
1x + 3y = $470 
Notice these values are in dollars not tickets. 
Now pick one equation and solve for one variable. We will use the x variable and the first equation. 
X + y = 292 
Get x by itself to find the equality by subtracting y from both sides. 
X = 292 - y 
Now we have a value for x that we can use to solve the second equation. Plug the right side of the equation in for the x value since they are equal
1(292-y) + 3y = 470 
Now solve for y 
292 - y + 3y = 470 
2y + 292 = 470 
2y = 178
Y = 89$ 
Now use this value for y in the second equation again. 
X + 3(89) = 470
X + 267 = 470 
X = 203$ 
This means that student ticket sales totals 203$ while non student totals 89$ 
In this specific case this also means that:
Student tickets sold = 203 tickets
Non student tickets sold = 89 tickets