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 This topic has been viewed 1146 times and has 1 reply
a068247

Joined: Jul 20, 2006
Posts: 1
Status: Offline

 [Jul 20, 2006 2:30:04 PM] [Link]
pskinner

Joined: Apr 2, 2005
Posts: 797
Status: Offline
 Re: Trying to solve inequality... Reply to this Post Reply with Quote

I tried your inequality using the 1D inequality solver/grapher,

6x+2(x-10)>8x-7,

Perhaps you did not understand the answer, which says that there are no solutions. It also indicated that when each side is rewritten and simplified, you can get -13>0, which is impossible and that is the reason why there are no solutions.

Let's take another look:

The left hand side reduces to: 6x+2x-20=8x-20.

So, you have: 8x-20>8x-7. Subtracting 8x from both sides you get:

-20>-7, which is impossible. This was rewritten by adding 7 to both sides and getting the equally impossible result: -13>0. Of course, doing things by hand, you don't really need that last step to see the answer.

Hope this explains what happened.
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Principal Skinner
 [Jul 20, 2006 6:53:40 PM] [Link]