The equation to find y would be 12y=72.
y is 6.
Since we know that the top and bottom line are parallel, and that the line going up and down is a transversal, we can assume that 72 and 12y equals the same number. (Visual representation shown in photo below.)
So the equation would be, 12y=72.
To find y, solve the equation.
First rearrange.
12y=72 --> 72/12 = y
Now, simplify.
72/12 = y
6 = y
And there you have it!
y is 6.
Hope this helps!
Let me know if you need anything else. :)