We start with an [b]acute[/b] triangle ABC and construct a square on each side. The altitudes of the triangle extended to the opposite sides of the corresponding squares cut each square in two rectangles.[br]Use the GeoGebra applet below to demonstrate the Law of Cosines: [math]c^2=a^2+b^2 – 2ab\; cos(\gamma)[/math].[br][br][br][br]This applet is based on the article “The Cuoco Configuration” by Roger E. Howe, The American Mathematical Monthly, Vol. 120, Dec. 2013, 916- 923.