x=number of senior tickets
y=number of student tickets
1st day
7x+1y=101
2nd day
7x+12y=134
easy, we can eliminate the x's
multiply first equation by -1
-7x-1y=-101
7x+12y=134 +
0x+11y=33
11y=33
divide by 11 both sides
y=3
sub back
7x+y=101
7x+3=101
minus 3 both sides
7x=98
divide both sides by 7
x=14
senior tickets cost $14
student tickets cost $3
that sounds unfair