Khan/khan-exercises — Issue #14049: Solving for a variable - How did you get the -1 at the end to simplify?
Author: KhanBugz
Created: 2012-02-17 03:14:06+00:00
State: open
Labels: chrome, hard, win7

Isolate the e.

e⋅(3f−3g−5)=−10f−5
e=−10f−53f−3g−5

We can simplify this by multiplying the top and bottom by −1.

e=10f+5−3f+3g+5

"How did you get the part to simplify with the -1"

[solving_for_a_variable.html?seed=182&problem=ABCD_EF](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=182&problem=ABCD_EF&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/solving_for_a_variable.html?seed=182&problem=ABCD_EF&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22None%20of%20the%20above.%5C%22%22%2C376%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C6%5D%2C%5B%22hint-activity%22%2C%220%22%2C19%5D%2C%5B%22hint-activity%22%2C%220%22%2C23%5D%2C%5B%22hint-activity%22%2C%220%22%2C25%5D%2C%5B%22hint-activity%22%2C%220%22%2C37%5D%2C%5B%22hint-activity%22%2C%220%22%2C50%5D%2C%5B%22hint-activity%22%2C%220%22%2C78%5D%5D)

["None of the above."]

Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.77 Safari/535.7

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