Youth tickets(y) cost $2 for a ride, while adult tickets(x) cost $3. the amount of money earned is $54. if all the seats were filled(24 seats), how many of each ticket was sold?

There are no constants here. But we have x and y here.
We will create an equation which is:
2y+3x=54.
But we will also create a second equation which states the number of seats.
x+y=24.

Now we do the two-equation solving method.
2y+3x=54
-2(x+y=24)

2y+3x=54
-2x-2y=-48

x=6

To solve for y, plug in x into one of the original equations. Which one doesn't matter.

y+6=24
y=18