Let R be the area of rectangle ABCD and
T the area of triangle APQ (where P and
Q are points on sides BC and CD of ABCD
respectively).

What is the minimal value of |BP|+|DQ|
in terms of R and T?

Note: R and T are constants with 0 < T ≤ R/2.
Therefore, |BP| and |DQ| are not independent variables
(i.e. if P varies between B and C, then Q
must vary between C and D such that T
stays constant).