Question 772465
Senor citizen ticket = x
Child's ticket = y
4x + 2y = 80...1
5x + 7y = 145...2
Multiply (1) by 5
Multiply (2) by 4
20x + 10y = 400...3
20x + 28y = 580...4
Subtract (3) from (4)
      18y = 180
        y = 10
Substitute y = 10 into (1)
4x + 2y = 80
4x + 2(10) = 80
4x + 20 = 80
4x = 80 - 20
4x = 60
x = 15.
Children's tickets cost $10
Senior citizen's tickets cost $15
Hope this helps.
:-)