Khan/khan-exercises — Issue #15284: Solving for a variable - VARIABLES QUESTION 30
Author: KhanBugz
Created: 2012-03-03 03:51:45+00:00
State: open
Labels: ie8, win7, wrong-or-unclear

Reporter: SHEARER4FAITH@EMBARQMAIL.COM

WHEN ADDING A NEGATIVE TO A POSITIVE SUCH AS -3 TO 16 WHY DID THE ANSWER COME UP -19 INSTEAD OF POSITIVE 13

[solving_for_a_variable.html?seed=113&problem=ABC_DEF](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=113&problem=ABC_DEF&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=113&problem=ABC_DEF&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22%3CCODE%20style%3D%5C%5C%5C%22DISPLAY%3A%20none%5C%5C%5C%22%20type%3D%5C%5C%5C%22math%2Ftex%5C%5C%5C%22%3Es%20%3D%20%5C%5C%5C%5Cdfrac%7B-20u%20%2B%209t%7D%7B13%7D%3C%2FCODE%3E%5C%22%22%2C251%5D%2C%5B%22incorrect-activity%22%2C%22%5C%22%3CCODE%20style%3D%5C%5C%5C%22DISPLAY%3A%20none%5C%5C%5C%22%20type%3D%5C%5C%5C%22math%2Ftex%5C%5C%5C%22%3Es%20%3D%20%5C%5C%5C%5Cdfrac%7B-20u%20%2B%209t%7D%7B-13%7D%3C%2FCODE%3E%5C%22%22%2C15%5D%2C%5B%22incorrect-activity%22%2C%22%5C%22None%20of%20the%20above.%5C%22%22%2C11%5D%2C%5B%22correct-activity%22%2C%22%5C%22%3CCODE%20style%3D%5C%5C%5C%22DISPLAY%3A%20none%5C%5C%5C%22%20type%3D%5C%5C%5C%22math%2Ftex%5C%5C%5C%22%3Es%20%3D%20%5C%5C%5C%5Cdfrac%7B-20u%20-%209t%7D%7B19%7D%3C%2FCODE%3E%5C%22%22%2C5%5D%5D)

["s = \\dfrac{-20u + 9t}{13}","s = \\dfrac{-20u + 9t}{-13}","None of the above.","s = \\dfrac{-20u - 9t}{19}"]

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