Khan/khan-exercises — Issue #14136: Compound inequalities - sign reversed?
Author: KhanBugz
Created: 2012-02-18 18:43:02+00:00
State: open
Labels: firefox, wrong-or-unclear, xp

Reporter: szulau@gmail.com

Apologies if this is just a failure to comprehend the question (or general concept), but here goes...

Compound Inequalities Practice

−4b≤4 and 4b+4>12

Show Solution (Step 1) shows the first inequality as simplified into:

b≥−1

I believe it should simplify to:

b≤-1

Answer should be

b≤-1 and b>2

LOVE Khan Academy :)
Keep it up, and thanks!

[compound_inequalities.html?seed=99&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/compound_inequalities.html?seed=99&problem=0&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/compound_inequalities.html?seed=99&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Eb%E2%89%A4-1%3C%2Fcode%3E%20and%20%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3Eb%26gt%3B2%3C%2Fcode%3E%5C%22%22%2C74%5D%2C%5B%22hint-activity%22%2C%220%22%2C1%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C4%5D%5D)

["b≤-1 and b>2"]

Mozilla/5.0 (Windows NT 5.1; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

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