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)
5/3 = 10/r-1 // - 10/r-1
5/3-(10/r)+1 = 0
5/3-10*r^-1+1 = 0
-10*r^-1 = -8/3 // : -10
r^-1 = 4/15
-1 < 0
1/(r^1) = 4/15 // * r^1
1 = 4/15*r^1 // : 4/15
15/4 = r^1
r = 15/4
r = 15/4
| Log[4](13*5)= | | 3m-3=5m+29 | | X(9+y)+y=-3 | | F(-3)=1/2(-3)-1 | | 2x+x-(-2x)=2x+12 | | X/8=10/6 | | c=12n | | -2(9v-4)=-10v | | 11c-3c=12-20 | | 9/10=4/r | | 2=x/-3-7 | | P/3=5/2 | | 2(1-7m)=6(-2m+2) | | 6+18z-2=9z+17-4z | | -2(4x+12)=2+3(6-x) | | 2(1v-4)+3v=42 | | x^4+8x^2-12=0 | | x+2(4)=3 | | 5x=3y+10 | | 3x+7x=-240 | | 7(-8k+9)=-9k+16 | | -4+2=-8a-14 | | 8(x+6)=6x+74 | | 6n-2n=10n+6 | | X=3yz^2+4 | | M-5/8=-51/4 | | 5-8y=29 | | 15x-4=15x-12 | | -4m+9m=30 | | r+11+8y=29 | | 90+x=67 | | 10.6f=18.36+13.3f |