Well basically you just have to chose a number of sides for the side length of the square to be and move those many places to get another vertex of the square. For example if we have (-2,3) and we choose the side lengths to be 4 units than you could move 4 places up, down, left, or right to get the other vertices for the square
Hope that helps :)
I believe the last one about right triangles. That’s why Pythagorean Theorem works.
