A circle passes through point P (2, - 1) and is tangent to the straight line X-Y = 1. The center of the circle is on the straight line y = - 2x

A circle passes through point P (2, - 1) and is tangent to the straight line X-Y = 1. The center of the circle is on the straight line y = - 2x

Let the coordinates of the center of a circle be o (x, - 2x), then the distance from O to the point (2, - 1) is equal to the distance from O to the straight line X-Y = 1. The solutions of the equations are as follows: (x-1) ^ 2 + (Y + 2) ^ 2 = 2 or (X-9) ^ 2 + (y + 18) ^ 2 = 338