Khan/khan-exercises — Issue #5095: Derivatives 1 - Question won't accept correct answer
Author: KhanBugz
Created: 2011-10-27 19:30:59+00:00
State: open
Labels: firefox, win7

[derivatives_1.html?seed=99&problem=quadratic](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/derivatives_1.html?seed=99&problem=quadratic&debug)

["-x+4","-x-4","-x-4","(-x)-4"]

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0.1) Gecko/20100101 Firefox/7.0.1

MathJax is loaded, ready, queue length: 0