Consider a convex quadrilateral whose diagonals have lengths p,q and whose area is A.

What is the maximum area of a rectangle that circumscribes the given quadrilateral?

(In reply to a start by Larry)

Nice formula for the quadriliteral... One observation is, that if you do a small parallel motion for one of the diagonals, the area of the circumscribing rectangle stays the same, provided no diagonal hits a rectangle corner.

Posted by JLo on 2020-01-07 15:46:16