The distance from the moving point m to the fixed point a (- 3,0) is two times of the distance to the origin. The trajectory of the moving point m is a curve C. The equation of the curve C is obtained

The distance from the moving point m to the fixed point a (- 3,0) is two times of the distance to the origin. The trajectory of the moving point m is a curve C. The equation of the curve C is obtained

Y ^ 2 + (x + 3) ^ 2 = 4 * (y ^ 2 + x ^ 2) = = > y ^ 2 + (x-1) ^ 2 = 4 is a circle