Paper Route (opens in new tab)

Origami can solve general cubic equations! The method was developed by Italian mathematician Margharita Piazolla Beloch, who in 1936 found a way to use paper folding to construct the common tangents to two parabolas. Given two points p1 and p2 and two lines l1 and l2, we can, whenever possible, make a single fold (dashed line) that puts p1 onto l1 and p2 onto l2 simultaneously. This fold finds a common tangent to two parabolas: one with focus p1 and directrix l1, the other with focus p2 and d...