Need math help.

Post » Sun Sep 08, 2013 8:22 am

So I've been working this ridiculously simple problem for two days and I STILL haven't gotten it right once. It's really, really pissing me off because there's no reason why I shouldn't be able to solve this. It's the only one in the whole chapter I can't get. I've tried working it out at least 10 different ways. Can someone please work this out for me so I can see what I'm doing wrong?

7/(2x+1) - 8x/(2x-1) = -4

No matter how I work it out I either get 16x2-22x+11 = 0 or 12x2-22x+11 = 0 and I still haven't found a way to simplify it past that.

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Madeleine Rose Walsh
 
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Post » Sun Sep 08, 2013 11:32 am

x != +/- 0.5

7(2x-1) - 8x(2x+1) = -4(2x-1)(2x+1)

14x - 7 - 16x^2 - 8x = -16x^2 + 4

6x - 7 = 4

6x = 11

x = 11/6

https://www.youtube.com/watch?v=3YmMNpbFjp0
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Saul C
 
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Post » Sun Sep 08, 2013 3:12 pm

I feel so damn stupid right now. :facepalm:

Thanks man. I've been running off 4 hours of sleep every night and I have around 200 of these to do. It's really starting to get to my head.

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maddison
 
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Post » Sun Sep 08, 2013 1:03 pm

Putting my rusty algebra skills to work, I come up with x = 11/6

Ninja'd.

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Johanna Van Drunick
 
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