A set of points is such that each point is three times as far away from the y-axis as it is from the point (4,0).Then locus of the points is:

Explanation

Let `(h,k)` is the point that is 3 times as far away from `y`-axis as it is from the point (4,0).

Then,

`h = 3sqrt((h-4)^2+k^2)`

`=>h^2 = 9(h^2+16-8h)+k^2`

`=>8h^2-72h+k^2+144 - 0`

`=>8(h^2-9h+81/4-81/4)+k^2 = -144`

`=>8(h-9/2)^2+k^2 = 162-144`

`=>8(h-9/2)^2+k^2 = 18`

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