Let be a convex quadrilateral with , and . The diagonals intersect at point . Determine the measure of .
Let $ABCD$ be a convex quadrilateral with $\angle{DAC}= \angle{BDC}= 36^\circ$ , $\angle{CBD}= 18^\circ$ and $\angle{BAC}= 72^\circ$. The diagonals intersect at point $P$ . Determine the measure of $\angle{APD}$.
Školjka 
be a convex quadrilateral with 
, 
and 
. The diagonals intersect at point 
. Determine the measure of 
.