Locus of centers of conics through four points by geometry

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I found the solution to one of the interesting problems of conic sections a little while ago and then I searched through this site and found an analytical approach, I am now going to provide an engineering approach and I hope to get proof in the comments

We know that for five points in the plane, four of which do not lie on the same line, there is a single conic segment passing through these points, so there is an infinite number of conic sections that Passing through four points, the centers of this family of conic sections make a one-dimensional geometric shop that turns out to be a conical section. What I did was create five points of this conic cutting using a ruler and compass.

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We are looking for the geometric locale of the center of the conical section that passes through the points: $A,B,C,D$ The desired geometric locus is the conical section that passes through the following five points:

$P=AB∩CD$

$Q=AD∩BC$

$K=AC∩BD$

$M$ is mid point $B,D$

$N$ is mid point $A,C$