If it's not what You are looking for type in the equation solver your own equation and let us solve it.
m in (-oo:+oo)
-2*m-(5/6) = -13/30 // + -13/30
-2*m-(5/6)-(-13/30) = 0
13/30-2*m-5/6 = 0
-2*m-2/5 = 0 // + 2/5
-2*m = 2/5 // : -2
m = 2/5/(-2)
m = -1/5
m = -1/5
| -2m-3/5=-19/15 | | -2m-2/5=-22/5 | | -2m-1/2=-19/22 | | -2m+9=8 | | -2m+9=17 | | -2m+9+2/5m=37/5 | | -2m+8=47/6 | | -2m+7/9=-29/9 | | -2m+7=37/5 | | -2m+6/7=-38/21-6m | | -2m+6+5m=-18 | | -2m+5/6=29/6 | | -2m+5=6m+7/3 | | -2m+5=5m-72 | | -2m+5=47/11 | | -2m+4/9-4m=544/9 | | -2m+4=6 | | -2m+3/5+2/5m=83/5 | | -2m+3/4=57/44 | | -2m+2/3=68/3 | | -2m+2/3=-64/3 | | -2m+10=47/4 | | -2m+10+1/2m=7 | | -2m+1/5=-53/35 | | -2m+1/5=-23/35 | | -2m+1/2-7m=91/2 | | -2m+1=5/9 | | -2m+1=-1/3 | | -2m+1=-17 | | -2m+1+6m=17 | | -2k=1 | | -2k=-16/11 |