Khan/khan-exercises — Issue #12947: Line relationships - opposite reciprocal
Author: KhanBugz
Created: 2012-02-02 23:02:15+00:00
State: open
Labels: ie8, ie9, win7, wrong-or-unclear

Reporter: alexis.manns@gmial.com

I thought that when you find the perpendicular of a slope it is the opposite reciprocal and this is just opposit. m should actually be -1/2 and b should be -4

[line_relationships.html?seed=76&problem=perpendicular-graph](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/line_relationships.html?seed=76&problem=perpendicular-graph&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/line_relationships.html?seed=76&problem=perpendicular-graph&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%22-.5%5C%22%2C%5C%22-4%5C%22%5D%22%2C130%5D%2C%5B%22incorrect-activity%22%2C%22%5B%5C%22-1%2F2%5C%22%2C%5C%22-4%5C%22%5D%22%2C21%5D%2C%5B%22hint-activity%22%2C%220%22%2C12%5D%2C%5B%22hint-activity%22%2C%220%22%2C40%5D%2C%5B%22hint-activity%22%2C%220%22%2C42%5D%2C%5B%22hint-activity%22%2C%220%22%2C43%5D%2C%5B%22hint-activity%22%2C%220%22%2C44%5D%5D)

[["-.5","-4"],["-1/2","-4"]]

Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.3)

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