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)
3*b-3 = 21 // - 21
3*b-21-3 = 0
3*b-24 = 0 // + 24
3*b = 24 // : 3
b = 24/3
b = 8
b = 8
| x^2+.65=1.8x | | 4+2n=-16 | | -4k+5=-31 | | 2d+2=16 | | -4w+6=-6 | | 5t+3=63 | | x^2=-8x-7 | | 6-7d=62 | | 7-4w=-13 | | 2m+9=-13 | | -5+5w=-5 | | 4+2w=24 | | -6-6k=-72 | | -8-3t=-8 | | (x-3)/2=5 | | -9-6k=-15 | | 6m-10=-10 | | 6b+4=-14 | | 8+7m=-27 | | 8+3t=11 | | 7t-5=-75 | | x^2+2.8x-5=0 | | 4a+3=43 | | 1+4b=25 | | 2a+8=-2 | | 4k+9=-35 | | 4+2d=12 | | 6a+10=4 | | -2+2b=-18 | | -3n+10=-17 | | -6a+5=-7 | | 2-5d=47 |