http://www.architecturendesign.net/12-useful-math-hacks-that-they-didnt-teach-you-in-school
desprateseagull New member Jul 20, 2003 10,171 brighton, actually Apr 29, 2015 #1 http://www.architecturendesign.net/12-useful-math-hacks-that-they-didnt-teach-you-in-school
