Question

Find the equation of the circle concentric with the circle x²+y²-8x+6y-5=0 and passing through the point (-2,-7)

Answer 1

Given equation 

x² + y² - 8x + 6y - 5 = 0 .....(i)

It is comparable to equation 

x² + y² +2gx + 2fy + c , 0

g = -4,f = 3,c = -5

center of the circle of given egⁿ will be (4,-3) It is the center of the circle concentric with circle whose equation we have to find.

As in concentric circle the center is same

OB (distance)