Answer:
 The center of the circle is (7, 4) 
Explanation:
Use the midpoint formula to obtain the x- and y-coordinates of the midpoint, which is also the center of the circle.
 3 + 11
xm = h = ------------ = 7
 2
 1 + 7
ym = k = ------------ = 4
 2
The center of the circle is (7, 4)