What is The equation for locus of a point P for which the distance from P to (-4,0) is double the distance from P to X-Axis.

Plz explain.

given A(-4,0) and let locus of point P be (x,y)

and P is 'y' units distant from X-axis

also, given PA=2y

 PA²=4y²

(x+4)²+y² = 4y²

(x+4)² = 3y²

The locus is a pair of staright lines: (x+4-3^1/2y)(x+4+3^1/2y)=0

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regards

Ramesh