Baseball fans can buy $7 tickets to sit in the lawn section or 16 tickets for stadium seats

System of equations,

7L + 16S = 6920 (1)  

S = 3L + 20 (2)

Step-by-step explanation:

Given question is incomplete; here is the complete question,

Baseball fans can buy $7 to sit in the lawn section or $16 for stadium seats. Ticket sales at last night's game totaled $6,920. The number of stadium tickets sold was 20 more than 3 times the number of lawn tickets. In order to find out how many stadium tickets were sold, Kelsey is writing a SYSTEM OF EQUATIONS. What is the second equation ?

Let the number of lawn tickets sold = L

and the number of stadium tickets sold = S

Cost of one lawn ticket = $7

Therefore, cost of L tickets = $7L

Cost of one stadium ticket = $16

Therefore, cost of S tickets = $16S

Total sales of the tickets = $(7L + 16S)

Equation for the situation will be,

7L + 16S = 6920 (1)

Number of stadium tickets sold were 20 more than 3 times of lawn tickets.

S = 3L + 20 (2)