So since the degree of the inner top right one is 108, the degree to the one next to that (the one to the left of the 108) is 72 degrees.
This is because two degrees next to each other (next to each other as in that must both be under or over a parallel line and they have to be on opposite sides of the transversal line) will equal to 180.
Now that we know that the inner top left degree is 72, we have also figured out that (5y-3) will equal 72. So, the number we substitute y for will have to make the whole equation equal 72.
To find Y, we almost reverse the problem.
We plug in 72 where y is, but we divide 72 by 5 , which is 14.4. Then 14.4 +3 is 17.4. So, Y=17.4.
We also know that X is 72 because if (5y-3) equals 72, X is going to be the same. So, X=72.
