Find the coordinates of the circumcenter of the triangle with the given vertices.

Let coordinates be (x,y).

⇒x = \({-7-1-7 \over 3}\)

      = -5

⇒y = \({-1-1-9 \over 3}\)

      = \({-11 \over 3}\)

Hence coordinates are (-5, -11/3). 

x = 1/2(-7 +(-1))             y = 1/2(-9 +(-1))