If it's not what You are looking for type in the equation solver your own equation and let us solve it.
b in (-oo:+oo)
-2*b = 12 // - 12
-2*b-12 = 0
-2*b-12 = 0 // + 12
-2*b = 12 // : -2
b = 12/(-2)
b = -6
b = -6
| 20=.5x(2x+2) | | -16=-4/5u | | -3=a-10 | | b-8=-4 | | b-2=7 | | 1=n-3 | | m/-3=-4 | | b-6=-17 | | d+1=6 | | a+9=18 | | -5=k-10 | | -11=t-2 | | -4+w=1 | | k-10=-7 | | -3+x=4 | | 6=n-2 | | 4=m-8 | | b+4=-6 | | d+8=18 | | n/5=-4 | | 7+d=19 | | m/7=-5 | | -8+a=2 | | -7=n+3 | | t=rf | | -7n=-42 | | k-5=-10 | | a/-4=-6 | | 2+a=6 | | b/3=-2 | | x/-4=-6 | | 7w=-77 |