Khan/khan-exercises — Issue #12394: Algebra challenge - Alternative but correct answer is not accepted
Author: KhanBugz
Created: 2012-01-29 14:58:08+00:00
State: open
Labels: chrome, wrong-or-unclear

Reporter: henrikmidtiby@gmail.com

The two suggested solutions
(y+5) = 3(x+3)
(y+2) = 3(x+2)
which is generated by calculating the slope (a = 3) and inserting one of the known points.

The alternative solution
(y-4) = 3(x-0)
will also go through the requested points, but is not accepted as a solution.

Best regards,
Henrik Skov Midtiby

[algebra_challenge.html?seed=30&problem=two-points (point_slope_form)](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/algebra_challenge.html?seed=30&problem=two-points&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/algebra_challenge.html?seed=30&problem=two-points&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5B%5C%224%5C%22%2C%5C%223%5C%22%2C%5C%220%5C%22%5D%5D%22%2C12%5D%2C%5B%22hint-activity%22%2C%220%22%2C31%5D%2C%5B%22hint-activity%22%2C%220%22%2C31%5D%2C%5B%22hint-activity%22%2C%220%22%2C32%5D%5D)

[[["4","3","0"]]]

Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.2 (KHTML, like Gecko) Ubuntu/11.10 Chromium/15.0.874.106 Chrome/15.0.874.106 Safari/535.2

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