school x has 8 more points than school y, which can be represented in the equation x=y+8
school x has triple the points of school y can be represented in the equation 3y = x. Substitute x=3y into the first equation
x=y+8
3y=y+8
2y=8
y=4
insert y=4 into 3y=x
3y=x
12=x
x=12, y=4