Min.problem in a geometric problem

Suppose we have three points in the plane p^(i), i = 1,2,3 and calculate the point that lies closest to these three points. The min.problem is obtained by setting the square sum of the distance between the given points and the unknown point, p = (x, y), which gives

a) Calculate the points coordinates symbolic in Matlab( is it a min point? )

b) Try to interpret the results, for example, by graphically illustrating specific choices of p^(i), i = 1,2,3

I have no clue how to solve this problem.