""Backstage With Blackstone"" Six cards and dice provide a lesson in parity ""Positives and Negatives Battle"" The first battle in the war between the Positives and Negatives -3 +5 = 2. It's the only time the Positives win a battle. Repeat of a segment first shown in Episode 121. ""Music Video: Triangle Song"" A song about various types of triangles. ""Triple Play"" Matthew and Jamie compete in this Square One TV game show. ""Person on the Street"" A recycled segment asks people what a hypotenuse is. Mathnet: The Case of the Missing Air, Part 3