Answer:
(x -2)² +(y +4)² = 34
Explanation:
The center of the circle is the midpoint of the line segment:
S = (J +K)/2 = ((-1, -9) +(5, 1))/2 = (4, -8)/2 = (2, -4)
The radius of the circle is the distance between the center and either end point. We want the square of the radius for our formula.
r² = (5 -2)² +(1 -(-4))² = 9 +25 = 34
The equation of a circle with center (h, k) and radius r is ...
(x -h)² +(y -k)² = r²
Using the numbers we have found, the equation for circle S is ...
(x -2)² +(y +4)² = 34