Problem:
The figure below shows a polygon , consisting of rectangles and right triangles. When cut out and folded on the dotted lines, the polygon forms a triangular prism. Suppose that  and . What is the volume of the prism?

Answer Choices:
A. 
B. 
C. 
D. 
E. 
Solution:
When folded, point coincides with , point with , point with , and point with . The triangular prism can be oriented to have as the base and as the height. Note that , so is a right triangle with legs of lengths and , and an area of . The volume of a prism is the area of its base multiplied by its height, and so the volume is .

Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions