Khan/khan-exercises — Issue #12606: Quadrilateral angles - trapezoid
Author: KhanBugz
Created: 2012-01-31 22:33:10+00:00
State: open
Labels: firefox, win7, wrong-or-unclear

This may just be my ignorance, but how do you know for sure that this figure is a trapezoid?

[quadrilateral_angles.html?seed=26&problem=trapezoid](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/quadrilateral_angles.html?seed=26&problem=trapezoid&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/quadrilateral_angles.html?seed=26&problem=trapezoid&debug&activity=%5B%5B%22correct-activity%22%2C%22%5C%22144%5C%22%22%2C59%5D%5D)

["144"]

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

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