Khan/khan-exercises — Issue #11306: Congruent triangles 2 - Isosceles Congruent Triangles
Author: KhanBugz
Created: 2012-01-15 21:57:57+00:00
State: open
Labels: ie8, ie9, win7, wrong-or-unclear

Reporter: krystinaatownsend@stu.bakeru.edu

When working problems for the "Congruent Triangle 2" exercises, I encountered an geometry error. I was given 2 triangles that were congruent through SSS. The triangles were both given 2 sides of length 3.9, making them isosceles. One angle was given as 53 degrees, and one of the base angles was given as 63 degrees. This should not be possible, because that makes the other base angle 64 degrees. According to the base angle theorem, the base angles have to be equal.

[congruent_triangles_2.html?seed=70&problem=parr2](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/congruent_triangles_2.html?seed=70&problem=parr2&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/congruent_triangles_2.html?seed=70&problem=parr2&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%2263%5C%22%22%2C17%5D%2C%5B%22correct-activity%22%2C%22%5C%2264%5C%22%22%2C74%5D%5D)

["63","64"]

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