I didn't get to finishing the problem (I just got distracted from my exams lol) but here are the equations for each of the people, if it helps.
S=-6L-2n+198
L=-.25n+33
N=-3.2727L+118.8
Sorry I couldn't be of more help!
-I5I=-5 vs. I-5I= 5
The absolute value will stay the same for both negative and positive. The result will change depending on where you put your absolute value signs.
Answer: 
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Work Shown:

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Explanation:
The idea is to first get all the y terms to one side. I did this by subtracting 2y from both sides in the third step.
Then factor out y and divide both sides by (8x-2)
Afterward there's the optional steps of simplifying (as shown in the final two steps).
2x+6 = 20
take 6 from both sides
2x = 14
divide by 2 on both sides
x = 7
6x plus 3x plus 4 minus 2