Using a coordinate plane, we have points (x, y). If we want to represent more than one set of points we designate them as (x1,y1) and (x2, y2). Often, we need to calculate the distance between these two points. An equation that is commonly used to fulfill such a need is d=SQRT((x2-x1)^2+(y2-y1)^2))
where d is the distance between the two points and x1,x2,y1,y2 represent points arranged as (x1, y1) and (x2, y2).
The midpoint between these two points is represented by (Xmdpt, Ymdpt) and it is represented by (Xmdpt, Ymdpt) = ((x1+x2)/2 , (y1+y2)/2)