If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( r )
r = 0
r = 0
r = 0
r in (-oo:0) U (0:+oo)
48/r = 8/3 // - 8/3
48/r-(8/3) = 0
48/r-8/3 = 0
48*r^-1 = 8/3 // : 48
r^-1 = 1/18
-1 < 0
1/(r^1) = 1/18 // * r^1
1 = 1/18*r^1 // : 1/18
18 = r^1
r = 18
r = 18
| 11x+65=100+4x | | 10/9=20/u | | 6x-5=12x+19 | | 3y=12-x | | s*4-22=86 | | -0.5x+1.71=-0.3x+9.11 | | 9/16w=36 | | 8/7=y/14 | | -8-3x=-x-2 | | a/10=1/2 | | -5.1+1.7z=-8.5 | | 25(120x-160)+56=20 | | 3/z=12/20 | | -5(x+6)5=-10 | | 8(x-5)=3x+15 | | -9(x+4)=-6(x-3) | | 10z+4=10z+8-12 | | 3a+5=3a-5 | | 9x+7=7x+23 | | X/-1.5=27 | | 3/5x7/9= | | 6x+4y=450 | | 3+5a=3+4a | | 3/5g--1/3=-10/3 | | -4.4=1.1y+1.1 | | x-0.18= | | 2a=12-2b | | -3x=-6x+4 | | x^3+2x^2-29x+20=0 | | 4/6-2/7= | | -4x+-8=12 | | ln(6x)=x |