Originally Posted by
arunforce
I don't think I've ever done a two column proof, but the three squares are congruent and the triangle is equilateral, and each square shares an edge with the triangle so they simply have to be the same length.
I guess a two column proof would go like this
DC = CE = ED, because the triangle is equilateral
AB = BC = CD = DA = CN = NM = ME = EC = EF = FG = GD = DE, because the squares share a side with a triangle, and by definition a square had equal length sides
therefore sqrt(AB^2+AB^2) = AE & sqrt(AB^2 + AB^2) = CF & sqrt(AB^2 + AB^2) = DN, because triangle and each segment is equal to any other segment.
AE = CF = DN, because they are all computed using the same formula