If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( c )
c = 0
c = 0
c = 0
c in (-oo:0) U (0:+oo)
6/18 = 4/c // - 4/c
6/18-(4/c) = 0
6/18-4*c^-1 = 0
-4*c^-1 = -1/3 // : -4
c^-1 = 1/12
-1 < 0
1/(c^1) = 1/12 // * c^1
1 = 1/12*c^1 // : 1/12
12 = c^1
c = 12
c = 12
| 6y+14=20-7y | | x^3=21x+50 | | 8x^2+120x+450= | | 75+25t=40t | | 200=f/4 | | 6.3/x=18/5 | | 1/2(4h+8)=30 | | 200/f4 | | 1.2/m=3/5 | | 102/8.5 | | 28x^2-84x+63= | | 3(-1.42)-y=0 | | 5/9=6/r | | b/7=-8 | | 3/4x-2/5y=10 | | 3(2x-1)=x+3x-1 | | v+0.2=8 | | 77/x^2=19/x+6 | | x=2(-3x+0)-10 | | m/7.08=-100 | | 5z=15 | | 10-x=-2 | | n/6+4=10 | | 4(7)+y=32 | | 7x+9=9(x+1)-2x | | 82/6 | | 48x^2+24x+3= | | x/9+5/x=2 | | 5x-4+8x+10=38 | | 9x=14x^2 | | 185/5 | | -4x+32=x-3 |