Question 1074446
I did the same, got 
x^4 + 12x^3 - 328x^2 + 432x + 1296 = 0
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I used a graph to find x.
x =~ 3.0405155
--> the x side is 6 plus that, or that can be the y side, they're interchangeable.
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I'm looking for another method, don't have one yet.