Answer: I think it might be 1933.
Step-by-step explanation
I hope it helped if not sorry. :/
9^2 < 6^2 + 8^2
so its acute angled.
One leg is horizontal, on the line y=3. Another leg is vertical, on the line x=1. The point where these intersect, D(1, 3) is the vertex of a right angle. Any right triangle inscribed in a circle has its hypotenuse as the diameter of the circle.
Since the triangle is a right triangle, the circumcenter is the midpoint of the hypotenuse: ((8, 3) + (1, -5))/2 = (4.5, -1).