Let x represent the price of one adult ticket
Let y represent the price of one child ticket
We were told that on the first day of ticket sales, the school sold 5 adult tickets and 3 child tickets. The cost wof these tickets would be 5x + 3y
Given that the total amount was $100, it means that
5x + 3y = 100
Also, the school took in $37 on the second day by selling 2 adult tickets and 1 child ticket. This would be expressed as
2x + y = 37
y = 37 - 2x
If we substitute y = 37 - 2x into 5x + 3y = 100, it becomes
5x + 3(37 - 2x) = 100
5x + 111 - 6x = 100
5x - 6x = 100 - 111
- x = - 11
Dividing both sides by - 1, it becomes
x = 11
y = 37 - 2x = 37 - 2 * 11
y = 37 - 22
y = 15
Thus, the cost of one adult ticket is $15 and the cost of one child ticket is $11