Word Problem: Solve by modeling the situation with a linear system.

At a recent production of A Comedy of Errors the Community Theater brought in a total of $30,495 in revenue. If adult tickets were $9 and children's tickets were $6.50 how many tickets of each type were sold if 3800 tickets in all were sold?

Question

Word Problem: Solve by modeling the situation with a linear system.  

At a recent production of A Comedy of Errors the Community Theater brought in a total of $30,495 in revenue.  If adult tickets were $9 and children's tickets were $6.50  how many tickets of each type were sold if 3800 tickets in all were sold?

anonymous · Answer

c=childs tickets
a=adults tickets

you're given the total sold so

a+c=3800

and the total revenue plus price for each ticket

9a+6.50c=30495

now you can solve by substitution or elimination

anonymous · Answer

so im not sure how to set this up..
a + c = 3800
9a + 6.50c = 30495

I use elimination and I get something totally wrong.  multiple the top by -9 for example, eliminate the a's.