Using a system of equations, it is found that there were 4,000 children tickets sold.
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
For this problem, the variables are given by:
The attendance at the amusement park is 5,000 attendees, hence:
x + y = 5000 -> y = 5000 - x.
Considering the cost of parking and that the total money earned by the park is $100,000, we have that:
15x + 40y = 100000
Applying the multiplication of the matrices, these equations are the same that the system gives. Replacing the second equation into the first:
15x + 40(5000 - x) = 100000
25x = 100000
x = 100000/25
x = 4000.
More can be learned about a system of equations at https://brainly.com/question/24342899
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