Explanation:
Let "x" be the number of senior tickets and "y" be the number of student tickets.
1st day: 2x + 7y = 40
2nd day: 8x + 2y = 56
(I am going to solve this by elimination and using addition because I find that easier.)
First, we are going to get rid of "y":
2 (2x + 7y = 40) -7 (8x + 2y = 56)
= 4x + 14y = 80 = -56x - 14y = -392
( We multiply the second equation by "-7" so that we can cancel "y")
Now add the equations:
4x + 14y = 80
-56x - 14y = -392
= - 52x = -312
Now divide -312 by -52
= x = 6
Now subsitute 6 in for "x" in the first equation:
2(6) + 7y = 40
= 12 + 7y = 40
Subtract 12 from each side:
= 7y = 28
Divide 7 from each side:
= y = 4
Answer:
x = 6
y = 4
Hope that helps! :D