\angle OXP = \angle HYP = 90^{\circ}\,\,$(OX$\,\,\perp\,\,$AB and\,\,$HY$\perp\,\,$AB)$
\therefore XO \parallel YH\,\,$(co-interior angles are supplementary)$
$Furthermore,$
\angle XOH = \angle YHO = 90^{\circ}\,\,(XY \parallel OH,\,\,$co-interior angles are supp.)$
$As all angles are right...