Khan/khan-exercises — pull request #23962 by beneater (2012-06-14 22:10:05+00:00)
Title: Add area_1 exercise and refactor area_of_squares_and_rectangles to be less algebra-y

New: [area_1](http://sandcastle.khanacademy.org/media/castles/beneater:area/exercises/area_1.html)

Changed: [area_of_squares_and_rectangles](http://sandcastle.khanacademy.org/media/castles/beneater:area/exercises/area_of_squares_and_rectangles.html)
Previously: [area_of_squares_and_rectangles](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/area_of_squares_and_rectangles.html)