Given a non-isosceles triangle \(ABC\) with incenter \(I\) and circumcircle \(\omega\). Denote the midpoints of arcs \(BC, AC, AB\) that does not contain the opposite vertex by \(X,Y,Z\) respectively. Denote \(P\) the midpoint of arc \(BC\) containing \(A\). Denote the intersection of \(BP\) and \(ZX\) as \(M\) and the intersection of \(XY\) and \(CP\) as \(N\). Prove that

Quadrilaterals \(BXIM\) and \(XCNI\) are kites.

\(MIN\) are collinear and \(XI\) is perpendicular to \(MN\).

## Comments

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TopNewestThey are two cyclic kites meaning symmetric pair of angles are right,which directly implies the second property – Xuming Liang · 1 year ago

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@Alan Yan Can you also post some more geometry problems ? – Shrihari B · 11 months ago

Yea even i did it that way ... although in the second part i could first prove the second statement and then the collinearity. This was a nice geometry problemLog in to reply

I m not able to understand the location of point N as intersection of BC and CP makes point C as point N – Harmanjot Singh · 1 year ago

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