The proof of this remarkable theorem is also remarkably straightforward. First, slice each polygon into triangles. Second, turn each triangle into a rectangle, similar to how Gina rearranged the ...

Image caption, The faces of a prism are the congruent polygon ‘ends’, plus the rectangles that join them. The number of rectangular faces is equal to the number of sides of the polygon cross ...

The polygon shape of the cross-section may be ... Image caption, Next work out the areas of the rectangular faces. The area of a rectangle is length multiplied by width. 7 × 3 = 21, 7 × 4 ...

Polygons can be grouped based the number of ... Oh of course, the Square, hi. Rectangle, who you doing? Rhombus, always a pleasure. Parallelogram, charmed. Kite! Looking great.