Find the centre and radius of the circles x2 + y2 – 8x + 10y – 12 = 0.

Question

Philoid · Accepted Answer

The given equation is

x2 + y2 – 8x + 10y – 12 = 0

or (x2 – 8x) + (y2 + 10) = 12

or (x2 - 8x + 16) + (y2 + 10y + 25) = 12 + 16+ 25

or (x – 4)2 + (y + 5)2 = 53

Therefore, the given circle has centre at(4, -5) and radius .

Find the centre and radius of the circles x² + y² – 8x + 10y – 12 = 0.