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caizza5

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Joined: Jun 6, 2007
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inequality stuff

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I can graph these problems and so I know the answers but I dont know how to actually solve it step by step, if someone can help that would be GREAT!
x^2+2x>0
x^2+4x-1x-4<0

[Jun 11, 2007 2:16:09 PM]

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pskinner

Joined: Apr 2, 2005
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Re: inequality stuff

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I can graph these problems and so I know the answers but I dont know how to actually solve it step by step, if someone can help that would be GREAT!
x^2+2x>0
x^2+4x-1x-4<0

One way is to solve each inequality separately and then take the intersection. For example, using a sign chart, you can find (by factoring) that:

x(x+2)>0

when x>0 and x>-2(which means x>0) or when x<0 and x+2<0 (which means x<-2). So, the first inequality is satisfied if either x<-2 or x>0.

Now, do the same for the other equation and take the intersection of the sets (so both inequalities are being satisfied).
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Principal Skinner

[Jun 11, 2007 4:07:31 PM]

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