Create an Equation....

Question

The circus is coming to town and Sue is selling tickets. The first day she sold 4 senior citizen tickets and 2 children's tickets for a total of $80. The second day she received $145 for 5 senior citizen tickets and 7 children's tickets. What is the price of a child's ticket and a senior citizen ticket?

I have no idea where to start with this to come up with an answer or equation...

Answer 1

1. 4s + 2c = 80   [ s is for senior , c is for children]
2. 5s + 7c = 145
3. use substitution method by taking the value of s from equation 1 
4.  s = (80- 2c)/4 = (40- c)/2
5. 5 (40-c)/2 + 7c = 145
6. 5(40-c) + 14c =     290
7. 200 -5c +14c = 290
8.  9c = 90
9. c = 10
10. s = (40-c)/2
11. s= 15
12. c = 10 , s =15