Think of the tune to “Pop Goes the Weasel.” Now sing these lyrics: Neg-a-tive b, plus or minus The square root of b squared mi-nus four a c All! over two a This jingle has helped generations of algebra students recall the quadratic formula that solves every equation of the form $latex ax^2+bx+c=0$. The formula is as useful as it is likely to appear in the dictionary under “math anxiety...