Devon purchased tickets to an air show for 7 adults and 2 children. The total cost was $173. The cost of a child's ticket was $8 less than the cost of an adult's ticket. Find the price of an adult's ticket and a child's ticket.
Please show work! Thanks

Respuesta :

Let 
C=child ticket
A=adult ticket

then
A=C+8 ........(1)
and
7A+2C=173 ......(2)
Substitute (1) in (2)
7(C+8)+2C=173
distribute
7C+56+2C=173
isolate C and solve
9C=173-56=117
C=$13
hence adulat
A=$13+$8=$21.