9514 1404 393
Answer:
(0.75, -1)
Explanation:
The center of the circle is at the midpoint of any diameter segment. The midpoint formula can be used.
C = (A +B)/2
C = ((-1, 1) +(2.5, -3))/2 . . . . fill in A and B
C = (-1+2.5, 1-3)/2 . . . . . . . add the coordinates
C = (1.5, -2)/2 . . . . . . finish the addition; next, divide by 2
C = (0.75, -1) . . . . . . the center of the circle