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k in (-oo:+oo)
20 = k+8 // - k+8
20-k-8 = 0
12-k = 0 // - 12
-k = -12 // * -1
k = 12
k = 12
| b+8=19 | | y+12=4/5(x+6) | | -9=d-8 | | -3m=-24 | | 15=d+4 | | 8=k+8 | | 9+w=12 | | -10+n=-6 | | w/6=5 | | 0=k+3 | | d/7=-6 | | 6=d+6 | | t+2=-3 | | b-10=-10 | | 0=b+3 | | t+7=15 | | t-7=-5 | | 17=t+7 | | 8+b=6 | | a-5=-16 | | k/5=-5 | | m+8=4 | | m+9=10 | | d/-3=4 | | n-2=-11 | | b/4=-2 | | t-8=-7 | | 10+t=4 | | 2t=-6 | | k+8=5 | | 2+m=2 | | 13=n+10 |