The answer is the option b: b. [tex]\left \{ {{S-4V=0} \atop {S+V=30,000}} \right. \\[/tex]
The explanation is shown below:
1. You have that S represents the number of tickets for the Spartans and V represents the number of tickets for the visiting team's fans, and the seating capacity of the Spartan Stadium is 30,000. Therefore, the total number of tickets is 30,0000:
[tex]S+V=30,000[/tex]
2. If the Spartans get four times as many tickets as the visiting team, you have:
[tex]S=4V[/tex]
[tex]S-4V=0[/tex]
3. If you solve the system of equations by the method of substitution, you obtain:
[tex]S+V=30,000[/tex]
[tex]4V+V=30,000[/tex]
[tex]V=6,000[/tex]
4. Calculate S:
[tex]S+6,000=30,000[/tex]
[tex]S=24,000[/tex]