Answer:
a + c = 20
15a + 10c = 225
Step-by-step explanation:
If 'a' is the number of tickets for adults and 'c' is the number of tickets for children, we can write the following equation:
a + c = 20
Because Mr. Ramirez purchased a total of 20 concert tickets.
In the same way, if the cost of the tickets is $15 for adults and $10 for children, we can write the following equation:
15a + 10c = 225
Because 15a is the total cost for adults, 10c is the total cost for children and 225 is the total cost in general.
Therefore, the system of equations that represents the given scenario is:
a + c = 20
15a + 10c = 225