Khan/khan-exercises — Issue #11739: Trigonometry challenge - right triangle assumed?
Author: KhanBugz
Created: 2012-01-20 22:17:43+00:00
State: open
Labels: firefox, lion, other

Reporter: amontgomery@rusd.k12.ca.us

I am in the trig challenge and did not do other modules - just checking things out. I have come across more than one item having to do with right triangle trig where I am verifying that it is a right triangle first, because it is not indicated in the problem nor diagram - is this how it was meant to be set up? Should students think about this (is this a right triangle?) before applying what they know about right triangles(?), as this is a common error students make once they start learning how to apply trig in non-right triangles. If it "looks" like a right triangle, then it is erroneously assumed to be a right triangle. I am not sure whether there are items where the triangle is NOT a right triangle. I hope this is making sense! :) If there is a rationale behind leaving out the indication of the right angle, please let me know. I want to learn as much as I can about this method of delivering content and instruction.
Respectfully,
Anne Marie Montgomery

[trigonometry_challenge.html?seed=70&problem=cosTrig1 (trigonometry_1)](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_challenge.html?seed=70&problem=cosTrig1&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_challenge.html?seed=70&problem=cosTrig1&debug&activity=%5B%5D)

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