If it's not what You are looking for type in the equation solver your own equation and let us solve it.
a in (-oo:+oo)
-5*a = -60 // + 60
60-5*a = 0
60-5*a = 0 // - 60
-5*a = -60 // : -5
a = -60/(-5)
a = 12
a = 12
| -9=w-4 | | -6+k=-7 | | 3=t-5 | | -5=t-6 | | a/2=-7 | | t+9=7 | | 5m=-5 | | 16=b+5 | | -8=a-4 | | 6=d-2 | | -3+n=9 | | t/2=-4 | | 3=b+9 | | d-3=0 | | -9+n=-19 | | d-8=0 | | 7=t+3 | | -11=w-5 | | -9+n=-4 | | -18=b-10 | | w-1=-13 | | t-1=10 | | -9+k=1 | | 2k=24 | | 7b=-7 | | 3t=-3 | | -6n=-24 | | -3=k-2 | | -7-5k=4k-61 | | 4a-7=125-7a | | 5t-4=4t+4 | | -2n-5=-26+5n |