Quadrilateral with Maximum Area

Given a quadrilateral ABCD with a fixed angle at A and fixed lengths for BC and CD. Construct ABCD such that it has the maximum area.

That is, points B and D would be located on the respective rays of angle A so that BC and CD are the sides opposite angle A and the area is a maximum. For example, the following figure shows a quadrilateral satisfying the conditions but probably NOT with the maximum area.