If it's not what You are looking for type in the equation solver your own equation and let us solve it.
w in (-oo:+oo)
3*w+4 = 40 // - 40
3*w-40+4 = 0
3*w-36 = 0 // + 36
3*w = 36 // : 3
w = 36/3
w = 12
w = 12
| -2-7d=-44 | | 5k-4=21 | | -5k+2=-8 | | 3+6b=-45 | | -4-6d=-76 | | 5d-5=50 | | 5t-2=43 | | -5b+2=-53 | | 10-2t=-4 | | -6d+9=45 | | 2+5w=-13 | | -8-6a=4 | | 2+7a=58 | | -4t-7=-23 | | 5w+2=27 | | 5b-9=31 | | -7t+2=-82 | | 2b+5=27 | | 7k+9=-75 | | -6w+5=-1 | | 4m+7=19 | | -5w+4=29 | | 5m-4=-64 | | 4b+10=42 | | 10+7x=-18 | | 7t-2=68 | | -2+5m=-37 | | -6-5a=-46 | | -3+2n=1 | | 5b+6=-24 | | -8+7w=41 | | 6w+1=-41 |