How To: Prove that the areas of diagonal-generated triangles are equal in geometry

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to demonstrate that a diagonal line drawn from one corner of a rectangle to another will generate two equivalent triangles.