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k in (-oo:+oo)
-15 = k-7 // - k-7
7-k-15 = 0
-k-8 = 0 // + 8
-k = 8 // * -1
k = -8
k = -8
| d+3=-3 | | -7n=-7 | | 2+6n=-8 | | w+3=13 | | -1=t+2 | | 5+b=12 | | 2+n/6=-8 | | 5m=-60 | | 12=b+8 | | -6=k+2 | | -7=w-8 | | 12=n+10 | | 7=d+3 | | k/6=5 | | t+5=7 | | w+6=-2 | | 10+k=-2 | | -10+b=-8 | | 4+k=7 | | -7m=-21 | | -13=n-1 | | -15=n-5 | | d/-3=-2 | | 1=w-9 | | w/-6=-1 | | 2=m+2 | | 15=m+4 | | -8+m=0 | | -7=k+2 | | w-4=-16 | | b+5=-5 | | -6*x^2+5*x-6=0 |