I'm not sure how to give you solid proof, like an equation or something, but you can see that out of the four coordinates, two of them have the y-value of 4 and two of them have the y-value of 2. Also, there is 1.5 in between each x-value that is paired with the same y-value... if that makes sense. So for (0.5, 2) and (3, 2), there is 1.5 in between 0.5 and 3. I hope this helps! Sorry it's a bit of a weird answer
