The quadratic formula is really useful, but its derivation is confusing to many. Like what is the point of "completing the square" anyway? In this video, I show how "completing the square" has a geometric interpretation--you are actually making the areas of two squares equal to each other!

Blog post (text/image summary): http://wp.me/p6aMk-4kG

You can read more about the history of the quadratic formula and its geometric roots from Cornell Mathematics professor David W. Henderson: http://www.math.cornell.edu/~dwh/pape...

While researching this post, I came across a website that offers a visual interpretation of the quadratic formula that helped me design the graphics: https://sites.google.com/site/butwhym...

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