Circle a triangle whose base has the length of the circle's circumference and whose height equals the circle's radius, which comes to multiplied by the radius squared: Equivalently, denoting diameter by "d", that is, approximately 79% of the circumscribing square (whose side is of length "d"). The circle is the plane curve enclosing the maximum area for a given arc length. This relates the circle to a problem in the calculus of variations, namely the isoperimetric inequality. Equation of a circle<br> In an "x"–"y" Cartesian coordinate system, the circle with centre coordinates ("a", "b") and radius "r" is the set of
The Penguin Goes Straight The Penguin Goes Straight The Penguin Goes Straight is the 21st episode of the "Batman" television series, first airing on ABC March 23, 1966. It guest starred Burgess Meredith as The Penguin. Attending a matinee performance at a Gotham City theatre, the Penguin foils a thief’s attempts to steal a ruby from the beautiful actress Sophia Starr. Then, at the Millionaire's Club, he stops two crooks from kidnapping millionaire Reggie Rich from a steam room. When Batman and Robin arrive, the Penguin announces his Penguin Protection Agency, which will protect the wealth of Gotham City's society crowd. Batman and Robin