i suppose you are talking about the point where vectors that perpendicularly bisect the sides of the triangle meet?

find such vectors and equate them. of course, here i am referring to the vector equations of lines. recall that we can represent a line by the equation:

where is a point the line passes through (in this case, the midpoint of the lines of the sides of the triangle, is a vector describing the direction of the line. in this case,the direction perpendicular to the sides they pass through, is a parameter, and is just the arbitrary vector

note that we can write the lines as follows:

get all you lines in this form and then equate the corresponding components. you will be able to solve for the parameters and hence find the point of intersection