Answer:
To find the radius of the circle, we need to complete the square for both x and y:
x2 + 10x + (5)2 + y2 - 12y + (6)2 = -10 + (5)2 + (6)2
This simplifies to:
(x + 5)2 + (y - 6)2 = 51
This is the equation of a circle with center (-5, 6) and radius √51.
So, the correct answer is (a) √51.