If it's not what You are looking for type in the equation solver your own equation and let us solve it.
k in (-oo:+oo)
(2/7)*k-8 = 7*k-(620/7) // - 7*k-(620/7)
(2/7)*k-(7*k)+620/7-8 = 0
(2/7)*k-7*k+620/7-8 = 0
564/7-47/7*k = 0 // - 564/7
-47/7*k = -564/7 // : -47/7
k = -564/7/(-47/7)
k = 12
k = 12
| 1/2+3/5a=-5a+493/90 | | -7t+2=t-10/3 | | 6x^4-14x^3+10x^2-1=0 | | 2/3+t=-6/7t+148/105 | | -t+2=-5t-6/5 | | 4n+8=13/2+7n | | -6t+1=t-37/12 | | 6+1/6m=6m+181/36 | | 6x+10=-2x+102/7 | | -1/2+3/4a=5a-10/3 | | 1/7w+4=6w+99/35 | | 4-1/5k=-7k+37/5 | | 5a+2=-a-34 | | 7b+1/3=-101/21-5b | | -2/3-5d=-4/5d-83/30 | | m+7=-3/5m+139/25 | | 8-3k=-2k+7 | | 1/7d+10=398/63-4d | | -x+3=-2/7x+58/21 | | (-10)2+(3a)2= | | 1/3-3/5b=5/7b+173/105 | | 1/7b+1/2=7b-1145/14 | | -5t+1/2=-2/5t-9/5 | | 2-3/5m=5/6m+197/120 | | 2k-8/9=4k+100/9 | | 1/9-t=2/3t-74/9 | | -7m-9=4m-20 | | 6a+2/3=-8/3+a | | -4/7t+8/9=-t+191/63 | | -2/7d-1/2-2/7d=-31/14 | | -1/10+a+2a=269/10 | | 5t+5/7-7t=61/7 |