Let a=price of the adult ticket for each adult
Let s=price of the student ticket for each student
Now, write the system of equations: We have 2 variables and 2 equations. This is what is needed to solve for the variables. # of equations must equal # of variables.
First day: 7a+14s=252
Second day: 3a+7s=121
Solve for a by multiplying the Second day equation above by -2 First, rewrite the equations over.
First day: 7a+14s=252
Second day: -6a-14s=-2*121=-242
Now, add the First day and Second day equations to get:
a=10 (the s term drops out because zero times s = zero)
Plug a=10 back into either equation and solve for s.
Choose the First day equation:
7*10+14s=252
70+14s=252
14s=182
s=13
Answers are:
a = $10 = price of adult ticket
s = $13 = price of student ticket