Answer:
Senior Citizen Tickets Cost = $9
Child Tickets Cost = $8
Explanation:
Let price of senior ticket be "s", and
price of child ticket be "c"
5 senior ticket and 3 child ticket cost 69, so we can write:

Also, 1 senior and 8 child tickets cost 73, thus we can write:

Or

We can put this into 1st equation and get an equation in terms of "c" and solve for c first:

Thus, c = 8
Now,
s = 73 - 8c
s = 73 - 8(8)
s = 73 - 64
s = 9
So,
Senior Citizen Tickets Cost = $9
Child Tickets Cost = $8