9514 1404 393
Answer:
(1, 2)
Explanation:
PR and QR are vertical and horizontal line segments, respectively. Then ΔQPR is a right triangle, and segment PQ is the hypotenuse. As such, segment PQ is also a diameter of the circumcircle, and its midpoint is the circumcenter.
Circumcenter = (P+Q)/2 = ((4, 0) +(-2, 4))/2 = (2, 4)/2
Circumcenter = (1, 2)