Y by Adventure10, Mango247
in the acute triangle
.
M is a point in the interior of the segment AC and N is a point on the extension of segment AC such that MN=AC.
let D,E be the feet of perpendiculars from M,N onto lines BC,AB respectively
prove that the orthocentre of
lies on circumcircle of 

M is a point in the interior of the segment AC and N is a point on the extension of segment AC such that MN=AC.
let D,E be the feet of perpendiculars from M,N onto lines BC,AB respectively
prove that the orthocentre of

