The properties of straight lines that issue from the point of intersection of the diagonals of a trapezoid, and are perpendicular to its legs

David Fraivert, Moshe Stupel
2015 Zenodo  
We present four theorems with their proofs, which have to do with the dropping of perpendiculars to the sides of a trapezoid from the point of intersection of the diagonals. Two of the theorems are actually new indicators for the fact that the quadrilateral in which certain characteristics hold is a trapezoid. We also consider whether the converse theorem is also true, as well as different geometric properties that result from the theorems.
doi:10.5281/zenodo.3978178 fatcat:kplfiq22jjcmljylj7kg5cxr54