Product of the diagonals in a convex quadrilateral(Bretschneider's formula for diagonals)

Description

A quadrilateral is a polygon with four sides (or edges) and four vertices or corners. In any convex quadrilateral ABCD, the product of the two diagonals is related to the four sides AB, BC, CD, DA and to the two of the oppsosite angles of the quadrilateral.

Related formulas

Variables

pOne of the diadonals of the quadrilateral (m)
qThe other diadonal of the quadrilateral (m)
aSide of the quadrilateral (AB) (m)
cSide of the quadrilateral (CD) (m)
bSide of the quadrilateral (BC) (m)
dSide of the quadrilateral (DA) (m)
AAngle of the quadrilateral (inside a and d) (m)
CAngle of the quadrilateral (inside b and c) (m)