If the opposite sides of a square are (-2,3) & (8,5).Then find the equations of sides.(without taking angles)

As the two opposite vertices of the square are given we can calculate the slope of the diagonal because the two opposite vertices form a diagonal of the square. The angle between the diagonal and the side is 45 degrees. So by using the formula forthe angle between two lines we can calculate the slope of the side

on calculating, slope of the diagonal comes to be 1/5 and the slope of the side comes to be -2/3 and 3/2. These are the slopes of the two opposite perpendicular sides of tha triangle which intersect at one of the given points. Now by using the slope point form we can calculate the equation of the two lines and hence all the sides. This question can only be done with the help of angles. If it can be done by some other method which does not involve the use of angles then I would like to know it.

opposite vertices?