Khan/khan-exercises — Issue #7478: Solving for a variable - Incorrect simplification
Author: KhanBugz
Created: 2011-12-01 19:13:46+00:00
State: open
Labels: lion, safari, wrong-or-unclear

Reporter: peterb@gmail.com

In solving this problem, a final simplification is made, multiplying both the numerator and denominator by -1. But, this is a completely unnecessary "simplification", and in fact complicates the answer significantly.

[solving_for_a_variable.html?seed=104&problem=ABCD_EF](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=104&problem=ABCD_EF&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=104&problem=ABCD_EF&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22None%20of%20the%20above.%5C%22%22%2C177%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%2C%5B%22hint-activity%22%2C%220%22%2C13%5D%5D)

["None of the above."]

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