If it's not what You are looking for type in the equation solver your own equation and let us solve it.
d in (-oo:+oo)
d/3 = 7 // - 7
d/3-7 = 0
1/3*d-7 = 0 // + 7
1/3*d = 7 // : 1/3
d = 7/1/3
d = 21
d = 21
| w+8=4 | | -2/3k=-1/9 | | 1+a=0 | | -7-8=-4+x | | 4x+7x+11=8x-6x+19 | | 73044*x=65739 | | y=2y-20 | | x-5=-11/2 | | -33/4=n-9 | | 65739*x=73044 | | a-6=-46/9 | | x-0.1=8.5 | | b-2=-14/9 | | n-2/5=-32/5 | | -39/7=n-6 | | k-1=-17/10 | | 450000-22000x=450000 | | log(x)+log(x-17)=log(110) | | -11+7=m-6 | | 2/3+m=1 | | m/5=-6/7 | | 2/9+b=-25/9 | | 65739=73044/x | | b+9/10=19/10 | | 45/28=k+6/7 | | 3/10=x+9/10 | | 1/10=t+1/2 | | d+6=-3 | | -45/44=a-3/4 | | 7b=14/3 | | w+8=95/11 | | d+8/9=17/9 |