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)
(2/3)*d-(4/7) = 100/21 // - 100/21
(2/3)*d-(4/7)-(100/21) = 0
(2/3)*d-4/7-100/21 = 0
2/3*d-16/3 = 0 // + 16/3
2/3*d = 16/3 // : 2/3
d = 16/3/2/3
d = 8
d = 8
| -2/3k-4=-24/7 | | 5/7w+4/7=4/7 | | 2+7k=8 | | 4/5-2/3k=32/15 | | 3/7b-1/4=89/28 | | -w+2/5=-28/55 | | 5x=9y | | -1-7x=-64 | | 5/7m-2/5=41/210 | | 4/5x+9=47/5 | | 1/3-w=25/3 | | -1/4-3/4b=13/2 | | 10+3x-16x^2=0 | | 8+1/4a=43/4 | | 1-4a=17 | | 1-7k=-62 | | 4/5-4a=-216/5 | | 6m+3/8=531/8 | | 5+6/7b=-1/7 | | -1/4-3n=-107/44 | | 2k+3/10=-157/10 | | 8+4t=52/5 | | 2/3x+2=47/18 | | 3b+1/2=-1/6 | | 6k-1/2=-37/2 | | 6b-2=-56 | | 6m-6=-3 | | 3/5+3a=13/5 | | 3/8+d=3/4 | | 4/5m+3/10=-23/110 | | -3/7b-3/5=-243/280 | | -6m-6=-12 |