Using a system of equations, it is found that:
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variables are:
Peter pays $50 for 1 orchestra and 4 balcony tickets, hence:
a + 4b = 50 -> a = 50 - 4b.
Justine pays $150 for 3 orchestra and 12 balcony tickets, hence:
3a + 12b = 150.
a + 4b = 50 -> a = 50 - 4b.
The equations are equal, hence we suppose that the costs are equal, that is:
a + 4b = 50 -> 5a = 50 -> a = 10.
Hence:
More can be learned about a system of equations at https://brainly.com/question/24342899
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