published on: 2012-06-24 19:19:01
we-just-love-boys.tumblr.com/post/25795250286/
▲= b² - 4.a.c
we-just-love-boys.tumblr.com/post/25802382046/
we-just-love-boys.tumblr.com/post/25806630142/
we-just-love-boys.tumblr.com/post/25807376771/
we-just-love-boys.tumblr.com/post/25807618273/